[Federal Register: September 16, 2004 (Volume 69, Number 179)]
[Proposed Rules]
[Page 55895-55927]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16se04-26]
[[Page 55895]]
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Part III
Department of Transportation
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National Highway Traffic Safety Administration
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49 CFR Parts 571 and 585
Federal Motor Vehicle Safety Standards; Tire Pressure Monitoring
Systems; Controls and Displays; Proposed Rule
[[Page 55896]]
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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
49 CFR Parts 571 and 585
[Docket No. NHTSA 2004-19054]
RIN 2127-AJ23
Federal Motor Vehicle Safety Standards; Tire Pressure Monitoring
Systems; Controls and Displays
AGENCY: National Highway Traffic Safety Administration (NHTSA), DOT.
ACTION: Notice of proposed rulemaking.
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SUMMARY: This notice of proposed rulemaking (NPRM) proposes to
establish a new Federal motor vehicle safety standard mandating tire
pressure monitoring systems capable of detecting when a tire is
significantly under-inflated. A prior version of the standard, adopted
by the agency in June 2002 in response to a mandate in the
Transportation Recall Enhancement, Accountability and Documentation
Act, was vacated by a decision issued by the U.S. Court of Appeals for
the Second Circuit in August 2003. This NPRM, which is consistent with
the Court's decision, proposes to require installation in new light
vehicles of a tire pressure monitoring system capable of four-tire, 25-
percent under-inflation detection. This proposed rule differs from the
final rule also in that it tentatively responds to issues raised in
petitions for reconsideration of the June 2002 final rule and proposes
to require a TPMS malfunction indicator.
DATES: Comments must be received on or before November 15, 2004.
ADDRESSES: You may submit comments identified by DOT DMS Docket Number
NHTSA 2004-19054 by any of the following methods:
Web site: http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://dms.dot.gov. Follow the instructions for
submitting comments on the DOT electronic docket site.
Fax: 1-202-493-2251.
Mail: Docket Management Facility; U.S. Department of
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401,
Washington, DC 20590-001.
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal Holidays.
Federal eRulemaking Portal: Go to http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.regulations.gov.
Follow the online instructions for submitting
comments.
Instructions: All submissions must include the agency name and
docket number or Regulatory Identification Number (RIN) for this
rulemaking. For detailed instructions on submitting comments and
additional information on the rulemaking process, see the Public
Participation heading of the Supplementary Information section of this
document. Note that all comments received will be posted without change
to http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://dms.dot.gov, including any personal information provided.
Please see the Privacy Act heading under Rulemaking Analyses and Notice
regarding documents submitted to the agency's dockets.
Docket: For access to the docket to read background documents or
comments received, go to http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://dms.dot.gov at any time or to Room PL-
401 on the plaza level of the Nassif Building, 400 Seventh Street, SW.,
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday,
except Federal Holidays.
FOR FURTHER INFORMATION CONTACT: For non-legal issues, you may call Mr.
George Soodoo or Mr. Samuel Daniel, Office of Crash Avoidance Standards
(Telephone: 202-366-2720) (Fax: 202-366-4329).
For legal issues, you may call Mr. Eric Stas, Office of Chief
Counsel (Telephone: 202-366-2992) (Fax: 202-366-3820).
You may send mail to these officials at National Highway Traffic
Safety Administration, 400 Seventh Street, SW., Washington, DC 20590.
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Executive Summary
II. Background
A. The TREAD Act
B. The June 2002 Final Rule Requiring TPMSs
1. The Notice of Proposed Rulemaking
2. The Preliminary Determination About the Final Rule
3. OMB Return Letter
4. Highlights of the June 2002 Final Rule
C. Petitions for Reconsideration of the June 2002 Final Rule
D. The Court of Appeals' Opinion
III. The Proposed Rule
A. Requirement for Four-Tire, 25-Percent Under-Inflation
Detection
B. Lead Time and Phase-In
C. Responses to Issues Raised in Petitions for Reconsideration
1. Replacement Tires
a. TPMS Malfunction Indicator
b. Owner's Manual Requirements Related to Replacement Tires and
the TPMS Malfunction Indicator
2. Spare Tires
3. Low Tire Pressure Telltale
4. Test Procedures
5. System Disablement
6. Instruction Manuals and Public Awareness Efforts
7. Reserve Load
8. Temperature-Corrected Inflation Pressure
9. Standardization of TPMS Parts
10. Definitions
11. Alternative Systems
IV. Benefits
V. Costs
VI. Regulatory Alternatives
VII. Public Participation
VIII. Rulemaking Analyses and Notices
I. Executive Summary
Court Decision and Agency Response
In August 2003, the U.S. Court of Appeals for the Second Circuit
(Second Circuit) vacated Federal Motor Vehicle Safety Standard (FMVSS)
No. 138, Tire Pressure Monitoring Systems, which NHTSA had established
by a final rule published in the Federal Register on June 5, 2002 (67
FR 38704). The rule required the installation of tire pressure
monitoring systems (TPMSs) in light vehicles, thereby implementing a
mandate in the Transportation Recall Enhancement, Accountability, and
Documentation (TREAD) Act of 2000 for a rulemaking to require systems
that warn consumers when a tire is significantly under-inflated.
The vacated standard covered an initial period from November 1,
2003 to October 31, 2006. Two compliance options were established for
this time period. Under the first option, a vehicle's TPMS would have
been required to warn the driver when the pressure in any single tire
or in each tire in any combination of tires, up to a total of four
tires, had fallen to 25 percent or more below the vehicle
manufacturer's recommended cold inflation pressure for the tires, or a
minimum level of pressure specified in the standard, whichever pressure
was higher. Under the second option, a vehicle's TPMS would have been
required to warn the driver when the pressure in any single tire had
fallen to 30 percent or more below the vehicle manufacturer's
recommended cold inflation pressure for the tires, or a minimum level
of pressure specified in the standard, whichever pressure was higher.
The agency stated in the document published in June 2002 that it
planned to issue the second part of the final rule by March 1, 2005.
The second phase was to establish performance requirements for the
period beginning on November 1, 2006. In the meantime, NHTSA planned to
leave the rulemaking docket open for the submission of new data and
analyses concerning the performance of TPMSs. NHTSA also decided to
conduct a study of real world performance of vehicles
[[Page 55897]]
equipped with TPMSs, which was nearly completed by the summer of 2003.
After issuance of the June 2002 final rule, three organizations
filed suit to challenge the TPMS regulation (FMVSS No. 138), in a case
before the U.S. Court of Appeals for the Second Circuit. The Second
Circuit issued its opinion in Public Citizen, Inc. v. Mineta) \1\ on
August 6, 2003.
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\1\ 340 F.3d 39 (2d Cir. 2003).
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The Court held that the agency's inclusion in the standard of a
one-tire, 30-percent compliance option was contrary to the intent of
Congress expressed in the TREAD Act. The Court found that that Act
unambiguously mandates TPMSs capable of monitoring each tire up to a
total of four tires, effectively precluding that option or any similar
option with less than a four-tire detection capability. While noting
that the agency must, as a general matter, consider the reasonableness
of cost in rulemaking regarding Federal motor vehicle safety standards,
the court also held that including the one-tire, 30-percent requirement
as an option was arbitrary and capricious under the Administrative
Procedure Act, given that the one-tire, 30-percent requirement was less
cost effective and that the agency did not sufficiently ``explain why
the costs saved were worth the benefits sacrificed.'' However, the
Court upheld the agency's use of a phase-in to implement the standard's
requirements and found that the agency had justification for adopting a
four-tire, 25-percent option instead of the four-tire, 20-percent
option proposed at an earlier stage of the rulemaking.
Consistent with the Second Circuit's opinion, NHTSA is proposing a
new FMVSS No. 138 that would include a requirement for four-tire, 25-
percent under-inflation detection. Most of the proposed standard's key
provisions and underlying reasoning remain the same as in the June 2002
final rule, with the obvious exception of the one-tire, 30-percent
option, which has been eliminated. In proposing this standard with its
performance requirement, NHTSA reiterates its intention to adopt a
standard that is technology-neutral and accommodates future
technological innovation.
We note that, if adopted, the approach outlined in this NPRM would
result in a consolidation of the rulemaking process, because, in light
of the Court's decision, it is no longer necessary to conduct Part II
of the rulemaking to determine longer-term compliance requirements
after October 31, 2006. Similarly, NHTSA also decided to terminate its
tire pressure survey designed to compare vehicles with direct and
indirect TPMSs to other vehicles without a TPMS. Under the
circumstances, the study's findings are no longer needed to help
determine an appropriate detection level.
Originally, the phase-in period for the TPMS standard was scheduled
to begin as of November 1, 2003. However, because the Court vacated the
standard in its entirety, the agency must promulgate an updated final
rule before a phase-in can commence. To determine the extent to which
vehicle manufacturers must alter pre-vacation product plans to comply
with the new final rule, the agency required all major automobile
manufacturers and TPMS suppliers to respond to Special Orders it issued
on September 9, 2003 (issued pursuant to 49 U.S.C. 30166(g)(1) and 49
CFR 510).\2\ This NPRM proposes to establish a new phase-in schedule,
accounting for these changed circumstances.
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\2\ In comments submitted to the Office of Management and Budget
related to the agency's Special Order, the Alliance of Automobile
Manufacturers (Alliance) suggested that its members' product plans
were predicated on the agency's amending the final rule in a manner
acceptable to its members (see Docket No. NHTSA-2000-8572-277).
Specifically, the Alliance in its September 5, 2003 letter stated,
``It is important to note that those plans were predicated on the
assumption that the major issues raised by the Alliance in its July
22, 2002 petition for reconsideration (with supplement on October
30, 2002) and its April 29, 2003 petition for rulemaking (with
supplement on June 30, 2003) of FMVSS 138 would be satisfactorily
resolved'' (emphasis in original). This expectation was repeated in
several vehicle manufacturer responses to the Special Order.
We believe that a clarification of the regulatory process is in
order. NHTSA carefully considers petitions for reconsideration of
final rules that raise new issues arising from resolution of matters
addressed in response to rulemaking proposals. After careful review,
the agency decides whether to grant the petitions and whether to
modify the rule. In any event, NHTSA's response to such petitions is
prospective. In the interim, the final rule remains effective as
originally promulgated. Because manufacturers cannot assume that
requested changes will be made in response to such petitions, they
must plan to comply with the final rule as issued, without
reservation. At the same time, the agency recognizes its
responsibility to grant or deny petitions for reconsideration of its
rules in a timely fashion.
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NHTSA is proposing the following phase-in schedule: 50 percent of a
vehicle manufacturer's light vehicles would be required to comply with
the standard during the first year (September 1, 2005 to August 31,
2006); 90 percent during the second year (September 1, 2006 to August
31, 2007); all light vehicles thereafter. This proposal would permit
carry-forward credits for vehicles certified as complying with the
standard that are produced after the effective date of the final rule.
As part of this NPRM, we also are addressing various issues raised
in petitions for reconsideration of the June 2002 final rule. At the
time of the Court's decision, the agency was nearing publication of its
responses to the petitions, and the majority of those issues remain
relevant to this updated TPMS rulemaking. Thus, we have decided to
address them here. Accordingly, we have proposed some modifications, as
compared to the vacated rule. These matters are discussed in further
detail below.
Response to Issues Raised in Petitions for Reconsideration
Petitions for reconsideration of the June 2002 final rule raised a
variety of issues, the more significant of them involving the
standard's requirement that a vehicle's TPMS must work with all
replacement tires of the tire size(s) authorized or recommended by the
vehicle's manufacturer. Concerns were expressed that the requirement
was overly broad and that some tire designs will prevent the proper
functioning of the TPMS. The petitions also provided information
indicating that there are as many as 600 tire models that could be used
as replacements on some vehicle models.
After considering the arguments raised in the petitions and the
supplemental information on TPMS compatibility with replacement tires,
we have tentatively decided to alter our approach to this topic.
Specifically, we are proposing only to require vehicle manufacturers to
assure compliance with FMVSS No. 138 with the tires installed on the
vehicle at the time of initial sale. We have tentatively decided upon
this approach for the following reasons.
First, information presented to NHTSA in the petitions shows that
there are currently over four million TPMS-equipped vehicles,\3\ and
neither the agency nor vehicle manufacturers have received reports
indicating any significant performance problems with those TPMSs when
replacement tires are installed on the vehicle. Further, there are a
variety of aftermarket TPMSs, and again, there has not been any
significant number of reports of incompatibility problems between those
systems and replacement tires. Thus, this significant real world
population suggests that TPMSs are expected to
[[Page 55898]]
continue to work with replacement tires in the vast majority of cases.
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\3\ Letter from Robert Strassburger, Vice President, Alliance of
Automobile Manufacturers, to NHTSA (October 20, 2003) (Docket No.
NHTSA-2000-8572-277).
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However, NHTSA has been presented with data demonstrating that a
very small number of replacement tires may cause a vehicle's TPMS to
exhibit functional problems for which there is currently no clear
solution. The identified problems are primarily related to the tires'
construction (e.g., run-flat tires) and material content (e.g., high
carbon content in low aspect-ratio tires, thicker sidewall, or steel
body ply sidewall).
In many instances, TPMSs may function properly even when equipped
with replacement tires with the above-mentioned characteristics, but to
date, it has not been possible to develop an appropriate performance
measure that would reliably identify those anomalous tires that would
prevent proper TPMS functioning. However, available data show that, in
2002, light vehicle tires having either steel body ply cords (steel
casing tires) or run-flat capability accounted for less than 0.5
percent of tires distributed in the United States.\4\
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\4\ Letter from Steven Butcher, Vice President, Rubber
Manufacturers Association, to NHTSA (October 31, 2003) (Docket No.
NHTSA-2000-8572-282).
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Based upon the above new information, we now believe that there is
not a sufficient basis to require vehicle manufacturers to assure
compliance with all replacement tires. While the number of tires
expected to be incompatible with a given TPMS is expected to be small,
such a requirement would nonetheless raise significant practicability
concerns. For example, vehicle manufacturers will not be able to
anticipate future tire construction changes; therefore, a replacement
tire requirement similar to the one contained in the June 2002 final
rule could force vehicle manufacturers to halt vehicle sales over a
problem they could not correct. We continue to believe, however, that
the TPMS should continue to function properly beyond the point at which
the vehicle's original tires are replaced, a clearly foreseeable event.
At a minimum, consumers need to know if the TPMS is not functioning
with the replacement tires. Otherwise, an unilluminated low tire
pressure telltale would give consumers a false sense of security in
those cases.
The Alliance has recommended a framework for resolution of the
problem of incompatible replacement tires, predicated upon a
requirement for a TPMS malfunction indicator coupled with a related
statement in the vehicle's owner's manual.\5\ We believe that this
approach could provide not only a relatively low-cost solution to the
replacement tire incompatibility problem, but also additional warnings
regarding other types of TPMS malfunctions (e.g., sensor damage, signal
attenuation, and dead batteries).
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\5\ Letter from Vann Wilber, Vehicle Safety and Harmonization
Director, Alliance of Automobile Manufacturers, to NHTSA (December
9, 2003) (Docket No. NHTSA-2000-8572-285).
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Therefore, in this NPRM, we are proposing to require the TPMS to be
equipped with a telltale that would alert the driver of a TPMS
malfunction, tire-related or otherwise. We are proposing that the
malfunction warning be provided either through a separate, dedicated
telltale or through a distinctive warning delivered by the low tire
pressure telltale.
In addition, we are proposing to require that the owner's manual
include a statement that would make consumers aware of this potential
problem. Specifically, we are proposing to require vehicle
manufacturers to alert consumers regarding: (1) Potential problems
related to compatibility between the vehicle's TPMS and various types
of replacement tires, and (2) the presence and operation of the TPMS
malfunction indicator.
Manufacturers also asked the agency to provide greater specificity
in the TPMS test procedures in order to increase objectivity. After
consideration of these recommendations, we are proposing to make the
standard's test procedures more specific. However, we also seek to
ensure that the test procedures continue to be broad enough to
replicate a range of real world driving conditions, rather than
encourage development of systems that are designed and tested for
effectiveness only in a narrow set of driving circumstances.
Specifically, we are proposing to designate a course for compliance
testing (i.e., the Southern Loop of the Treadwear Test Course), which
is both objective and representative of a range of driving conditions.
In addition, we are proposing to refine the calibration and system
detection provisions to specify that driving times in the designated
speed range will be cumulative (not continuous) and that system
calibration or low tire detection time will not accumulate during
periods when the brake is applied. Further, we also are proposing to
specify that the vehicle's tires will be shaded from direct sun when
parked. We believe that the proposed modifications would sufficiently
address calls for greater specificity in the standard's test
procedures, while ensuring that the TPMS will function on a variety of
roadways and road conditions.
In response to other issues raised in the petitions, we are
proposing to incorporate additional changes in this NPRM, including
revision of the definition of ``small volume manufacturer'' and
clarification of specific issues that may arise under FMVSS No. 138.
II. Background
A. The TREAD Act
Congress enacted the TREAD Act; \6\ on November 1, 2000. Section 13
of that Act \7\ required the Secretary of Transportation, within one
year of the statute's enactment, to complete a rulemaking ``to require
a warning system in new motor vehicles to indicate to the operator when
a tire is significantly under inflated.'' Section 13 also required the
regulation to take effect within two years of the completion of the
rulemaking. Responsibility for this rulemaking was delegated to NHTSA.
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\6\ Public Law 106-414, 114 Stat. 1800 (2000).
\7\ See 49 U.S.C. Sec. 30123 note (2003).
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B. The June 2002 Final Rule Requiring TPMSs
1. The Notice of Proposed Rulemaking
NHTSA initiated the TPMS rulemaking with the publication of a
Notice of Proposed Rulemaking (NPRM) on July 26, 2001 (see 66 FR 38982,
Docket No. NHTSA-2000-8572-30). That NPRM proposed to require passenger
cars, light trucks, multipurpose passenger vehicles, and buses with a
gross vehicle weight rating of 10,000 pounds or less, except those with
dual wheels on an axle, to be equipped with a TPMS.
The agency sought comment on two alternative sets of performance
requirements for TPMSs and indicated that it contemplated adopting only
one of them in the final rule. The first alternative would have
required that the driver be warned when the pressure in any single tire
or in each tire in any combination of tires, up to a total of four
tires, had fallen to 20 percent or more below the vehicle
manufacturer's recommended cold inflation pressure for the vehicle's
tires (the placard pressure), or a minimum level of pressure specified
in the standard, whichever was higher. (This alternative is referred to
below as the four-tire, 20-percent alternative.) The second alternative
would have required that the driver be warned when the pressure in any
single tire or in each tire in any combination of tires, up to a total
of
[[Page 55899]]
three tires, had fallen to 25 percent or more below the placard
pressure, or a minimum level of pressure specified in the standard,
whichever was higher. (This alternative is referred to below as the
three-tire, 25-percent alternative.)
There are two types of TPMSs currently available, direct TPMSs and
indirect TPMSs.\8\ Direct TPMSs have a pressure sensor in each wheel
that transmit pressure information to a receiver. In contrast, indirect
TPMSs do not have tire pressure sensors, but instead rely on the wheel
speed sensors, typically a component of an anti-lock braking system
(ABS), to detect and compare differences in the rotational speed of a
vehicle's wheels, which correlate to differences in tire pressure.
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\8\ We anticipate that new types of TPMS technology may be
developed in the future that will be capable of meeting the NPRM's
proposed requirements. For example, such systems might incorporate
aspects of both direct and indirect TPMS (i.e., hybrid systems). In
concert with TPMS suppliers, tire manufacturers might be able to
incorporate TPMS sensors directly into the tires themselves. In
proposing a performance standard, NHTSA is cognizant of and seeks to
encourage technological innovation.
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To meet the four-tire, 20-percent alternative within the timeframe
envisioned in the NPRM, vehicle manufacturers likely would have had to
install direct TPMSs because it is unlikely that even improved indirect
systems would be able to detect loss of pressure until pressure has
fallen 25 percent and to detect all combinations of significantly
under-inflated tires. To meet the three-tire, 25-percent alternative,
vehicle manufacturers would have been able to install either direct
TPMSs or improved indirect TPMSs.
2. The Preliminary Determination About the Final Rule
After consideration of the comments submitted in response to the
NPRM, NHTSA preliminarily determined to issue a final rule that would
have specified a four-year phase-in schedule and that would have
allowed compliance with either of two options during the phase-in
period (i.e., between November 1, 2003 and October 31, 2006). Under the
first option, a vehicle's TPMS would have had to warn the driver when
the pressure in one or more of the vehicle's tires, up to a total of
four tires, was 25 percent or more below the placard pressure, or a
minimum level of pressure specified in the standard, whichever pressure
was higher. (This option is referred to below as the four-tire, 25-
percent option.) Under the second option, a vehicle's TPMS would have
had to warn the driver when the pressure in any one of the vehicle's
tires was 30 percent or more below the placard pressure, or a minimum
level of pressure specified in the standard, whichever pressure was
higher. (This option is referred to below as the one-tire, 30-percent
option.) The minimum levels of pressure specified in the standard were
the same for both compliance options.
After the phase-in (i.e., after October 31, 2006), the second
option would have been terminated, and the provisions of the first
option would have become mandatory for all new vehicles. Thus, all
vehicles would have been required to meet a four-tire, 25-percent
requirement.
3. OMB Return Letter
After reviewing the draft final rule, OMB returned it to NHTSA for
reconsideration, with a letter explaining its reasons for doing so, on
February 12, 2002. For a discussion of that letter and NHTSA's analysis
of the issues it raised, see NHTSA's June 5, 2002 final rule at 67 FR
38704, 38712, 38718-22.
4. Highlights of the June 2002 Final Rule
Consistent with the OMB return letter, the agency divided the TPMS
final rule into two parts because it decided to defer its decision as
to which long-term performance requirements for TPMS would best satisfy
the mandate of the TREAD Act. This deferral was intended to allow the
agency to consider additional data on the effect and performance of
TPMSs currently in use.
The first part of the final rule was published in the Federal
Register on June 5, 2002 (67 FR 38704) (Docket No. NHTSA 2000-8572). It
established requirements for vehicles manufactured during the first
three years (i.e., between November 1, 2003 and October 31, 2006) and
phased TPMSs in by increasing percentages of production. The agency
stated that the second part of the final rule would establish
requirements for vehicles manufactured on or after November 1, 2006.
a. Part One--November 2003 Through October 31, 2006
The June 2002 final rule provided two compliance options during the
interim period. Under the first compliance option, vehicle
manufacturers would have been required to equip their light vehicles
(i.e., those with a GVWR of 4,536 kg (10,000 pounds) or less) with
TPMSs to warn the driver when the pressure in any single tire or in
each tire in any combination of tires, up to a total of four tires, is
25 percent or more below the vehicle manufacturer's recommended cold
inflation pressure for the tires, or a minimum level of pressure
specified in the standard, whichever pressure is higher. Under the
second compliance option, the vehicle's TPMS would have been required
to warn the driver when the pressure in any single tire is 30 percent
or more below the vehicle manufacturer's recommended cold inflation
pressure for the tires, or a minimum level of pressure specified in the
standard, whichever pressure is higher.\9\
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\9\ The minimum levels of pressure were the same for both
compliance options.
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The two compliance options were outgrowths of the alternative sets
of requirements proposed in the NPRM. In response to comments
indicating that current indirect TPMSs could not meet the proposed
three-tire, 25-percent under-inflation requirements, the agency adopted
the one-tire, 30-percent option. That option would have allowed those
systems to be used during the phase-in. The four-tire, 25-percent
under-inflation option could have been met by installing either direct
TPMSs or hybrid TPMSs (i.e., TPMSs that combine direct and indirect
TPMS technologies). One TPMS supplier indicated the potential for
developing and producing hybrid systems, although it also indicated
that it did not currently have plans for doing so.
The owner's manual for vehicles certified to either compliance
option would have been required to include an explanation of the
purpose of the yellow low tire pressure warning telltale, the potential
consequences of driving on significantly under-inflated tires, the
meaning of the telltale when it is illuminated, and the actions that
drivers should take in response.
To facilitate compliance with the options, the rule included a
phase-in of the standard's requirements by increasing percentages of
production. Ten percent of a vehicle manufacturer's light vehicles were
to be required to comply with either compliance option during the first
year (November 1, 2003 to October 31, 2004), 35 percent during the
second year (November 1, 2004 to October 31, 2005), and 65 percent
during the third year (November 1, 2005 to October 31, 2006). The
agency permitted carry-forward credits for vehicles that were
manufactured during the phase-in and equipped with TPMSs that comply
with the four-tire, 25-percent option.
NHTSA also provided in the June 2002 final rule that small volume
manufacturers would be given to the end of the phase-in period to
comply with the TPMS requirements. Later, similar treatment was
accorded to final stage manufacturers and alterers through a correcting
amendment to the
[[Page 55900]]
final rule published in the Federal Register.\10\ As with previous
phase-ins, NHTSA adopted reporting requirements to aid it in monitoring
the implementation of the phase-in. The agency included these reporting
requirements in 49 CFR Part 590.
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\10\ 68 FR 4107 (January 28, 2003).
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b. Part Two--November 2006 and Thereafter
The June 2002 final rule provided that beginning November 1, 2006,
all covered vehicles would be required to comply with the requirements
in the second part of the final rule. The agency stated its intention
to publish the second part of the final rule by March 1, 2005, in order
to provide sufficient lead time to manufacturers.
In anticipation of making its decision about long-term
requirements, the agency left the rulemaking docket open for the
submission of new data and analyses. The agency also committed to
conduct and place in the docket a tire pressure survey comparing the
tire pressures of vehicles without any TPMS to the pressure of vehicles
with TPMSs not complying with the four-tire, 25-percent performance
option. After consideration of the rulemaking record, as supplemented
by the tire pressure study and any other new information submitted to
the agency, NHTSA would issue the second part of the rule.
Based upon the record before the agency at the time of publication
of the first part of the final rule, NHTSA stated its tentative belief
that the four-tire, 25-percent option would best meet the mandate in
the TREAD Act. However, NHTSA remained open to the possibility of
obtaining or receiving new information sufficient to justify a
continuation of the compliance options established by the first part of
the final rule, or the adoption of some other alternative.
C. Petitions for Reconsideration of the June 2002 Final Rule
NHTSA received thirteen petitions for reconsideration of the June
5, 2002 final rule from: (1) Ferrari S.p.A.; (2) Delphi Auto, Inc.
(Delphi); (3) Japan Automobile Tyre Manufacturers Association, Inc.
(JATMA); (4) Johnson Controls, Inc.; (5) Volkswagen of America, Inc.
(Volkswagen); (6) Bureau de Normalisation de l'Automobile (BNA) ISO/
TC22; (7) Porsche Cars North America, Inc. (Porsche); (8) Alliance of
Automobile Manufacturers (Alliance); (9) Rubber Manufacturers
Association (RMA); (10) Aviation Upgrade Technologies; (11) Vehicle
Services Consulting, Inc. (VSC); (12) DENSO International America, Inc.
(DENSO); and (13) Maserati S.p.A.
The petitioners raised a variety of issues, including ones related
to the rule's requirements for functioning of the TPMS with replacement
tires, system calibration, tire reserve load, the compliance testing
procedures, system disablement and reset, the TPMS telltale (e.g.,
issues related to color, extinguishment time, reconfigurable displays,
and bulb check), definitions, alternative systems, and policy and
procedures for the second part of the rulemaking.
NHTSA was in the process of finalizing its responses to the various
petitions for reconsideration at the time of the Second Circuit's
decision. However, because the majority of the issues raised in the
petitions for reconsideration remain relevant, we have decided to
address them substantively in this proposed rule.
D. The Court of Appeals' Opinion
After issuance of the June 2002 final rule, Public Citizen, Inc.,
New York Public Interest Research Group, and the Center for Auto Safety
filed a suit challenging certain aspects of the TPMS regulation.
The Second Circuit issued its opinion in Public Citizen, Inc. v.
Mineta on August 6, 2003, which held that the agency's adoption in the
standard of a one-tire, 30-percent compliance option is ``contrary to
the intent of the TREAD Act and, in light of the relative shortcomings
of indirect systems, arbitrary and capricious.'' \11\ The Court found
that the TREAD Act unambiguously mandates TPMSs capable of monitoring
each tire, up to a total of four tires, effectively precluding the one-
tire, 30-percent option, or any similar option that cannot detect
under-inflation in any combination of tires up to four tires.
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\11\ 340 F.3d 39, 54 (2d Cir. 2003).
---------------------------------------------------------------------------
The Court concluded that, against a backdrop of more efficacious
performance of direct systems, current indirect systems (i.e., those
unable to meet a four-tire, 25-percent standard) are not sufficiently
effective as would permit NHTSA to allow automakers to install those
indirect systems in new motor vehicles.\12\ The court opinion went on
to note that the record, as reflected in NHTSA's final rule, suggested
that the four-tire, 25-percent option would not only prevent more
injuries and save more lives, but also that it would be more cost-
effective on a per-life, per-injury basis than adopting both options
together.
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\12\ The Court found that given current technological
limitations, indirect systems cannot meet the requirements of the
four-tire, 25-percent under-inflation option under the June 2002
final rule, and even under the one-tire, 30-percent compliance
option, indirect systems cannot detect low tire pressure in all
cases (e.g., when two tires on the same side of the vehicle or on
the same axle are under-inflated, or when all four tires are equally
under-inflated).
---------------------------------------------------------------------------
However, the Court stated that the agency was correct to consider
the relative costs of adopting or rejecting different compliance
options. Further, the Court did not preclude the use of indirect
systems, to the extent that they are able to meet the performance
requirements proposed in this NPRM. This point is noteworthy because it
is NHTSA's practice to issue performance standards that seek to give
manufacturers as broad a choice as possible in selecting the technology
to be used in meeting those standards. Thus, as TPMS technology
develops, it may become possible for new types of systems to meet the
proposed performance requirements.
In all of the other areas of challenge, the Court supported the
agency's actions. Specifically, the Court upheld NHTSA's use of a
phase-in as part of the TPMS final rule. The Court also held that
NHTSA's decision not to adopt the four-tire, 20-percent compliance
option proposed in the NPRM was not arbitrary and capricious. The Court
found that the agency had explained adequately that the four-tire, 25-
percent option may permit improved indirect TPMSs and hybrid TPMSs to
be used to comply with the standard and that this option was
substantially more cost-effective than the proposed four-tire, 20-
percent option.
Ultimately, the Court vacated the rule (FMVSS No. 138) in its
entirety and directed the agency to issue a new rule consistent with
its August 6, 2003 opinion. NHTSA published a final rule in the Federal
Register on November 20, 2003, vacating FMVSS No. 138. The agency
stated that, at present, vehicle manufacturer have no certification or
reporting responsibilities. 68 FR 65404.
III. The Proposed Rule
A. Requirement for Four-Tire, 25-Percent Under-Inflation Detection
This NPRM proposes to re-establish FMVSS No. 138, Tire Pressure
Monitoring System, in a manner consistent with the Second Circuit's
opinion. Specifically, it proposes to require passenger cars,
multipurpose passenger vehicles, trucks, and buses with a GVWR of 4,536
kg (10,000 pounds) or less, except those with dual wheels on an axle,
to be equipped with a TPMS to alert the driver when one or more of the
vehicle's tires, up to all four
[[Page 55901]]
of its tires, are significantly under-inflated. The rule proposes
requirements for covered vehicles manufactured on or after September 1,
2005 (i.e., Model Year (MY) 2006), subject to the proposed phase-in
schedule discussed below. The proposed standard is intended to be
technology-neutral so as to permit compliance with any available TPMS
technology that meets the performance requirements.
Because the Second Circuit vacated the entire TPMS standard in
striking down the one-tire, 30-percent option, it is necessary for
NHTSA again to propose the complete regulatory text for FMVSS No. 138.
The following points highlight the key provisions of the proposed
requirements.
The TPMS would be required to warn the driver when the
pressure in one or more of the vehicle's tires, up to a total of four
tires, is 25 percent or more below the vehicle manufacturer's
recommended cold inflation pressure for the tires, or a minimum level
of pressure specified in the standard, whichever pressure is
higher.\13\
---------------------------------------------------------------------------
\13\ As proposed, these minimum activations pressures (MAPs) are
included in Table 1 of the standard, which is identical to the Table
1 that appeared in the June 5, 2002 final rule. However, we note
that the Alliance submitted a Petition for Rulemaking on April 29,
2003 that asks NHTSA to make certain changes to the minimum
activation pressures in Table 1 (Docket No. NHTSA-2000-8572-265).
NHTSA is in the process of evaluating the issues raised in the
Alliance petition.
---------------------------------------------------------------------------
Vehicle manufacturers would be required to certify vehicle
compliance under the standard with the tires installed on the vehicle
at the time of initial vehicle sale.\14\
---------------------------------------------------------------------------
\14\ We note that some vehicle manufacturers authorize their
dealers to replace the vehicle's factory-installed tires with other
tires, including ones with a different size and/or recommended cold
tire inflation pressure. The TPMS would have to perform properly
with any such tires, because the vehicle could be equipped with
those tires at the time of initial sale. Of course, the manufacturer
would not have that responsibility if the dealer installed other
tires without manufacturer authorization. However, the dealer would
violate the Motor Vehicle Safety Act if it installed tires on a new
vehicle that prevented the TPMS from functioning properly. See 49
U.S.C. 30112(a).
---------------------------------------------------------------------------
The TPMS would be required to include a low tire pressure-
warning telltale \15\ (yellow) that must remain illuminated as long as
any of the vehicle's tires remains significantly under-inflated and the
vehicle's ignition locking system is in the ``On'' (``Run'') position.
The telltale must be extinguished when all of the vehicle's tires cease
to be significantly under-inflated.\16\ The TPMS's low tire pressure-
warning telltale would be required to perform a bulb-check at vehicle
start-up.
---------------------------------------------------------------------------
\15\ As part of this notice proposing to re-establish FMVSS No.
138, we are proposing to add two versions of the TPMS low tire
pressure telltale and a TPMS malfunction telltale to Table 2 of
FMVSS No. 101, Controls and Displays. The proposed regulatory text
in this NPRM incorporates the TPMS telltales in Table 2, as that
table currently exists in the Code of Federal Regulations. However,
we note that NHTSA published an NPRM in the Federal Register on
September 23, 2003 that proposes to update and expand FMVSS No. 101
(68 FR 55217). Publication of the present version of Table 2 here is
not intended to suggest a change in approach to the ongoing FMVSS
No. 101 rulemaking. We anticipate that the TPMS telltales would be
incorporated in a revised Table 2, once a final decision is reached
on updating Standard No. 101.
\16\ For some systems, extinguishment may occur automatically
upon re-inflation of the tires to the proper pressure. Other systems
may require manual reset in accordance with the vehicle
manufacturer's instructions. However, manual reset of the system may
not result in extinguishment of the low tire pressure telltale prior
to correction of the under-inflation situation.
---------------------------------------------------------------------------
The TPMS also would be required to include a malfunction
indicator to alert the driver when the system is non-operational, and
thus unable to provide the required low tire pressure warning. We are
proposing that TPMS malfunction could be indicated by either:
(1) Installing a separate, dedicated telltale (yellow) that
illuminates upon detection of the malfunction and remains continuously
illuminated as long as the ignition locking system is in the ``On''
(``Run'') position and the situation causing the malfunction remains
uncorrected, or
(2) Designing the low tire pressure telltale so that it flashes for
one minute when a malfunction is detected, after which the telltale
would remain illuminated as long as the ignition locking system is in
the ``On'' (``Run'') position. This flashing and illumination sequence
would be repeated upon each subsequent vehicle start-up until the
situation causing the malfunction has been corrected.
If the option for a separate telltale is selected, the TPMS
malfunction telltale would be required to perform a bulb-check at
vehicle start-up.
The TPMS would not be required to monitor the spare tire
(if provided), either when it is stowed or when it is installed on the
vehicle.
For vehicles certified under the standard, vehicle
manufacturers would be required to provide in the owner's manual an
explanation of the purpose of the low tire pressure warning telltale,
the potential consequences of significantly under-inflated tires, the
meaning of the telltale when it is illuminated, and what actions
drivers should take when the telltale is illuminated. Vehicle
manufacturers also would be required to provide a specified statement
in the owner's manual regarding: (1) Potential problems related to
compatibility between the vehicle's TPMS and various replacement tires,
and (2) the presence and operation of the TPMS malfunction indicator.
B. Lead Time and Phase-In
The Second Circuit decision vacating FMVSS No. 138, while affirming
the use of a phase-in as part of the TPMS rulemaking, necessitates a
change in the phase-in schedule in order to ensure the practicability
of the standard's implementation. First, for those vehicle
manufacturers that had intended to certify to the June 5, 2002 final
rule's one-tire, 30-percent option, redesign and a change in production
plans may be necessary in order to meet the proposed four-tire, 25-
percent detection requirements of this NPRM. Second, there must be an
adequate supply of TPMSs available that meet the proposed requirements
of the standard so that vehicle manufacturers would be capable of
meeting the phase-in requirements.
To help determine appropriate lead time and phase-in percentages,
NHTSA issued a number of Special Orders on September 9, 2003. NHTSA
issued Special Orders to 14 vehicle manufacturers to ascertain what
their production plans had been for compliance with the June 2002 final
rule, including the option(s) under which they intended to certify and
the technologies they intended to use in doing so. NHTSA also issued
Special Orders to 13 TPMS suppliers in order to determine their current
and planned production, as well as their current capacity and their
ability to produce beyond their current capacity. The majority of the
information submitted pursuant to these Special Orders is confidential
business information (CBI) under the relevant NHTSA regulation.\17\ We
believe that the information obtained in response to these Special
Orders provides the agency with the necessary data to propose and
ultimately set a fair and reasonable phase-in schedule.
---------------------------------------------------------------------------
\17\ 49 CFR Part 512 (as amended, 68 FR 44209 (July 28, 2003)).
---------------------------------------------------------------------------
From the responses to these Special Orders, NHTSA learned that, in
anticipation of the start of the phase-in under the June 2002 final
rule, most vehicle manufacturers were moving aggressively toward
installation of TPMSs capable of meeting the four-tire, 25-percent
detection requirement, but some were not. The information provided by
TPMS suppliers indicated sufficient capacity to supply TPMSs with a
four-tire, 25-percent detection capability in quantities that would
[[Page 55902]]
easily meet the newly proposed phase-in requirements.
Based upon the information obtained from the data submitted in
response to the Special Orders, NHTSA is proposing to adopt the
following phase-in schedule: 50 percent of a vehicle manufacturer's
light vehicles would be required to comply with the standard during the
first year (September 1, 2005 to August 31, 2006); 90 percent during
the second year (September 1, 2006 to August 31, 2007); and all
vehicles thereafter.\18\
---------------------------------------------------------------------------
\18\ The responses to the Special Orders also contained
information indicating that a 20% phase-in would be appropriate for
MY 2005. The agency, however, does not believe the rulemaking
process will be completed in time to allow for the adoption of a MY
2005 requirement, so we are not proposing one in this NPRM.
---------------------------------------------------------------------------
To encourage early compliance, NHTSA is proposing to permit carry-
forward credits for vehicles that are certified as complying with the
standard \19\ and that are manufactured on or after the effective date
of the final rule.\20\ However, beginning September 1, 2007, all
covered vehicles would be required to comply with the standard, without
regard to any earlier carry-forward credits.
---------------------------------------------------------------------------
\19\ Any such certification of compliance with the standard is
irrevocable.
\20\ The effective date of the amendments made to the Code of
Federal Regulations by the final rule would likely be specified as
30 days after the issuance of the final rule.
---------------------------------------------------------------------------
As before, NHTSA is proposing to exclude from the phase-in
requirements final stage manufacturers, alterers, and small volume
manufacturers (SVMs) (although the criteria for designation as an SVM
has been revised). We also are proposing to maintain the phase-in
reporting requirements, as modified to reflect the newly proposed
phase-in schedule.\21\ We request public comment on the schedule that
NHTSA has proposed.
---------------------------------------------------------------------------
\21\ Since the issuance of the June 5, 2002 final rule, NHTSA
has published an unrelated NPRM in the Federal Register that, in
part, proposes to consolidate the placement of phase-in reporting
requirements for various standards (including the TPMS standard) in
a renamed Part 585, Phase-in Reporting Requirements. See 68 FR 46546
(August 6, 2003). Consequently, in this notice, we are proposing
ultimately to incorporate the TPMS phase-in reporting requirements
as Subpart D to Part 585.
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C. Responses to Issues Raised in Petitions for Reconsideration
As noted previously, NHTSA was nearing the point of issuing its
response to petitions for reconsideration of the June 5, 2002 final
rule for TPMS, when the Second Circuit issued its opinion in Public
Citizen, Inc. v. Mineta. Most issues raised in the petitions for
reconsideration were not directly related to the one-tire, 30-percent
option nullified by the Court and thus remain relevant. Accordingly,
NHTSA decided to address those issues in this notice, as discussed
below.
1. Replacement Tires
As expressed in paragraph S4.4 of the standard, the June 5, 2002
final rule required that each TPMS-equipped vehicle meet the
requirements of FMVSS No. 138 when the vehicle's original tires are
replaced with optional or replacement tires (for simplicity of
discussion, we refer below to these tires as replacement tires) of the
size(s) authorized or recommended for use on the vehicle by the vehicle
manufacturer. Paragraph S6(l) set out test procedure provisions
applicable to replacement tires.
TPMS operation with replacement tires was the issue most frequently
raised and extensively discussed in the petitions for reconsideration.
Five petitioners (Delphi, DENSO, the Alliance, Johnson Controls, and
JATMA) raised this issue. The petitioners generally argued that the
standard's replacement tire requirements are not practicable because
there are a large number of replacement tires available in the tire
sizes authorized or recommended for each vehicle model and the
construction characteristics of some of those tires may prevent proper
functioning of the TPMS, even within a given size.
The Delphi petition asked us to amend FMVSS No. 138 S4.4 and S6(l)
so that manufacturers need only certify TPMS operation with replacement
tires that are of the same size and ``type'' recommended by the vehicle
manufacturer. According to Delphi, tire ``type'' is a critical factor
that will affect TPMS operation, and takes into account properties such
as construction, speed rating, and manufacturer's brand. Tire
``construction'' involves the number of plies and the material of the
plies in both the tread and the sidewall.
The Delphi petition argued that adding a tire type limitation to
the requirement for TPMS compliance with replacement tires is
necessary, not only from a practical standpoint, but in order to render
the standard objective, as required under the National Traffic and
Motor Vehicle Safety Act (49 U.S.C. Chapter 301) (Safety Act). The
Johnson Controls petition argued that the current, above-mentioned
provisions of the standard related to replacement tires are not
``reasonable, practicable, and appropriate,'' as required by section
30111(b)(3) of the Safety Act. It argued that the requirement for TPMS
compliance with the standard for all replacement tires would go beyond
the limitations of current TPMS capabilities.
Delphi argued that lack of specificity regarding the type of tire
would force manufacturers to anticipate future tire designs in order to
certify a vehicle under the TPMS rule, rendering the rule insufficient
to meet the objectivity requirements of the Safety Act. Further, Delphi
argued that in practical terms, without a tire type limitation,
manufacturers would have to certify certain TPMS-equipped vehicle
models for compliance with over 100 replacement tire options, if size
is the only limiting factor.
DENSO's petition expressed similar concerns and added that, for
indirect TPMSs, tire pressure sensitivity (i.e., the relationship
between tire radius and tire inflation pressure) is a design parameter
of significant operational importance. However, according to DENSO,
tire pressure sensitivity varies by tire manufacturer or brand even if
such tires are of an identical size, thereby making it difficult to
ensure that a TPMS would be able to comply with the standard for all
replacement tires of the specified size. According to the petitioner,
similar concerns apply to direct TPMSs because some aftermarket tires
are constructed with materials (e.g., steel) that, to varying degrees,
may shield the radio signal transmitted from the TPMS tire sensor to
the receiver. The DENSO petition asked NHTSA to limit the universe of
replacement tires for which manufacturers must certify TPMS
functionality under FMVSS No. 138 by revising paragraph S4.4 of the
standard to require vehicle manufacturers to certify TPMS compliance
only for tires released as original equipment.
The Alliance petition also objected to the final rule's requirement
that the TPMS operate properly with all replacement tires. The Alliance
argued that just because different brands and styles of the same size
tire meet the same tire industry standards, it does not mean that such
tires are equivalent in form and function. For example, it argued that
different tires of the same size are often designed to perform under a
variety of road and weather conditions, and at varying levels of
durability, performance, and cost. Thus, according to the petitioner,
there may be fundamental differences in tire construction, even though
such tires may meet the same basic performance standards. The Alliance
also stated in its petition that the current availability of
aftermarket direct TPMSs does not guarantee that these systems will be
sensitive to all tire constructions, and
[[Page 55903]]
such problems may be even more pronounced for indirect TPMSs.
In its petition, the Alliance argued also that the replacement tire
requirement is not practicable. According to the Alliance, there may be
hundreds of aftermarket tires of the same size as a vehicle's original
equipment tires, but in some cases, differences in tire properties may
pose insurmountable problems for proper functioning of the TPMS. It
argued that the mere existence of a non-compatible tire would render
compliance with S4.4 impossible. In addition, because tire
manufacturing is largely beyond the control of vehicle manufacturers,
the Alliance argued that it is unfair to ask vehicle manufacturers to
certify TPMS compliance with all replacement tires of a given size.
Finally, the Alliance contended that existing TPMSs work in an
acceptable fashion with replacement tires in the field and that the
agency has not provided any evidence to support an assumption to the
contrary.
The Alliance supplemented its petition with a letter providing data
intended to support its position that a vehicle's TPMS should not be
required to comply with FMVSS No. 138 with replacement tires. Among
other things, the letter provided data on the number of tires of the
same size for various vehicles and on characteristic differences
between original equipment and replacement tires of the same size. More
specifically, the Alliance presented data on the specifications for 33
replacement tires (P195/75R14), showing differences in overall diameter
and revolutions per mile, among other specifications. However, the
Alliance did not explain in its petition how these differences in
overall diameter and revolutions per mile, for each of the 33 tires,
affected compliance for vehicles with indirect TPMSs.
The supplementary letter also included data from a study of the
number of replacement tires that are available for a given vehicle
model. For 61 vehicle models, an average of 5 tire sizes are
recommended by the manufacturer, and an average of 162 different tire
models are available per vehicle. Data were provided to show also the
negative effect that steel reinforcement in the sidewall of a tire can
have on the signal transmission by direct TPMSs.
The Alliance also asserted that NHTSA has not established a safety
need that would justify requiring manufacturers to certify that TPMSs
will function with replacement tires. Alternatively, the Alliance
argued that if the agency does identify such a safety need, NHTSA
should undertake rulemaking to standardize and tighten the performance
requirements for replacement tires to ensure that their revolutions per
kilometer (RPK) profiles are within the range that can work with TPMSs
designed to meet the requirements of FMVSS No. 138.
The Alliance also argued that there is no precedent for such a
broad requirement, noting that manufacturers are not required to
certify vehicle compliance with FMVSS Nos. 105 and 135 for all
available replacement brake linings, or to certify vehicle compliance
with crashworthiness performance requirements for all aftermarket body,
restraint, or interior components. The Alliance and Johnson Controls
petitions also objected to high testing costs associated with the TPMS
requirements for replacement tires, which the Alliance estimates to be
between $3.2 million and $106.5 million.
Consequently, the Alliance requested that the agency revise FMVSS
No. 138 to delete paragraph S4.4, so that vehicle manufacturers are
only required to certify compliance with the TPMS standard with any
tire released as original equipment on the vehicle.
The JATMA petition took a view contrary to the other petitions
regarding TPMS compliance with replacement tires, urging NHTSA to
strengthen that portion of the standard so as to require the TPMS to
function properly even with tires of a type different than the standard
and optional tires recommended by the manufacturer. JATMA reasoned that
failure of the TPMS to function properly with such tires could lead to
significant confusion among consumers.
In a letter dated September 11, 2003, General Motors (GM) submitted
information to NHTSA intended to illustrate additional difficulties
associated with the TPMS standard's replacement tire requirement,
specifically problems associated with certifying run-flat tires with
direct TPMSs.\22\ According to GM, on the basis of validation testing,
it certified a MY 2004 vehicle equipped with run-flat tires to the
requirements of the June 5, 2002 final rule. However, the company later
decided to test the vehicle with a set of replacement run-flat tires.
During testing with those replacement tires, the TPMS produced a series
of erroneous warnings. GM stated that the root cause was an attenuated
signal from the TPMS sensors as a result of the replacement tires'
thicker sidewall construction. GM stated that its test further
demonstrates that it is not practicable to require vehicle
certification under FMVSS No. 138 for all replacement tires.
---------------------------------------------------------------------------
\22\ Docket No. NHTSA-2000-8572-275.
---------------------------------------------------------------------------
Since the Second Circuit's decision, NHTSA has continued to gather
information regarding the benefits and limitations of a requirement
that a TPMS continue functioning when any replacement tires of a size
recommended or authorized by the vehicle manufacturer are installed on
the vehicle. On October 20, 2003, the Alliance and several of its
members presented additional data regarding their research into direct
TPMS operation with replacement tires.\23\ Although by no means a
comprehensive analysis of all replacement tires, the Alliance data
identified 20 replacement tires with which the TPMS would reportedly
not function properly.
---------------------------------------------------------------------------
\23\ Docket No. NHTSA-2000-8572-277
---------------------------------------------------------------------------
The Alliance stated that there are a small number of replacement
tires that are problematic for direct TPMSs due to signal attenuation.
Problems may arise from aspects of tire design and construction, such
as high carbon content in low aspect-ratio tires, thicker sidewall, or
steel body ply sidewall. Some tires with these characteristics may
weaken the radio frequency signal from a direct TPMS's sensors to its
receiver, potentially resulting in inaccurate tire inflation pressure
information or overt failure of the system to operate. These data
suggest that the scope of the signal attenuation problem is broader
than just the issue of steel sidewall tires documented in earlier
Alliance submissions.
RMA also submitted information on the prevalence of tires with
characteristics identified as being incompatible with proper TPMS
functioning, at least in some cases. As noted above, these problems are
primarily related to the tires' construction (e.g., run-flat tires) and
material content (e.g., high carbon content in low aspect-ratio tires,
thicker sidewall, or steel body ply sidewall). According to the RMA, in
2002, light vehicle tires having either steel body ply cords (steel
casing tires) or run-flat capability accounted for less than 0.5
percent of tires distributed in the United States.\24\
---------------------------------------------------------------------------
\24\ Letter from Steven Butcher, Vice President, Rubber
Manufacturers Association, to NHTSA (October 31, 2003) (Docket No.
NHTSA-2000-8572-282).
---------------------------------------------------------------------------
In an effort to develop a test protocol to evaluate a tire's radio
frequency signal attenuation (the most significant problem for direct
TPMSs), the Alliance conducted an analysis of nearly 100 tires,
including 28 of the most popular replacement tires with 14, 15, and 16-
[[Page 55904]]
inch rim sizes.\25\ The Alliance stated that its testing included both
original equipment (OE) tires and high-volume, non-OE replacement
tires. According to the Alliance, the proper functioning of a TPMS is
dependent upon the interaction of the system's various components. It
said that factors such as wheel material, wheel shape, and the mounting
of the sensor in the wheel all can affect transmission of the TPMS
signal.
---------------------------------------------------------------------------
\25\ Letter from Vann Wilber, Vehicle Safety and Harmonization
Director, Alliance of Automobile Manufacturers, to NHTSA (December
17, 2003) (Docket No. NHTSA-2000-8572-287).
---------------------------------------------------------------------------
The Alliance presented its findings and a proposed solution to the
replacement tire issue in a December 9, 2003 letter to NHTSA.\26\ Based
upon the results of its testing, the Alliance reached two basic
conclusions. First, the Alliance stated that most replacement tires
were found to be compatible with the TPMS tested. Second, the Alliance
asserted that ``to date we have not been able to identify appropriate
performance measures that would reliably identify those few replacement
tires that are likely to undermine the proper functioning of tire
pressure monitoring systems.''\27\ The Alliance stated that other than
steel sidewall construction, there was no obvious construction or size
characteristics that distinguished run-flat, low profile, and non-steel
sidewall tires that permit proper TPMS functioning from those that
preclude proper TPMS functioning.
---------------------------------------------------------------------------
\26\ Letter from Vann Wilber, Vehicle Safety and Harmonization
Director, Alliance of Automobile Manufacturers, to NHTSA (December
9, 2003) (Docket No. NHTSA-2000-8572-285).
\27\ Id.
---------------------------------------------------------------------------
In its December 9, 2003 letter, the Alliance recommended that NHTSA
consider a two-step approach that would provide information to
consumers regarding replacement tire compatibility with TPMSs, as a
substitute for the replacement tire certification requirement. First,
the Alliance recommended that the vehicle owner's manual should contain
specified language alerting consumers to select appropriate replacement
tires that are compatible with the vehicle's TPMS. Second, the Alliance
recommended that NHTSA should require vehicle manufacturers to provide
an in-vehicle indication when there is inadequate signal reception from
one or more of the TPMS sensors (either through a dedicated telltale, a
separate function of the low tire pressure telltale, a message on a
reconfigurable display, or some other means). In an attachment to its
letter, the Alliance also provided draft regulatory language that would
implement its recommended approach.
After considering the arguments in the petitions and the
supplemental information on TPMS compatibility with replacement tires,
we have tentatively decided to alter our approach to this topic.
However, we emphasize that it would not be permissible for dealers to
install tires on a new vehicle that would take the vehicle out of
compliance with the TPMS standard. In addition, we are proposing to
only require vehicle manufacturers to assure TPMS compliance with the
tires installed on the vehicle at the time of initial vehicle sale.
However, we are proposing certain new requirements designed to address
the issue of continuing TPMS functionality, including incorporation of
a TPMS malfunction indicator and additional language in the owner's
manual discussing replacement tire compatibility with the tire pressure
monitoring system. The portions of our proposal related to replacement
tires build upon the approach recommended by the Alliance.
Several factors contributed to our decision to alter how we would
address the need to have the TPMS continue functioning properly after
the vehicle's original tires are replaced. First, information presented
to NHTSA shows that there are currently over four million TPMS-equipped
vehicles.\28\ Neither the agency nor vehicle manufacturers have
received reports indicating any significant performance problems with
those TPMSs when replacement tires are installed on the vehicle. In
addition, the agency has noted previously that aftermarket direct TPMSs
are available and that such systems may be capable of functioning
regardless of the construction of the tires.\29\ NHTSA does not have
any information to suggest a significant problem with the operation of
aftermarket TPMSs, although the performance capabilities of these
systems are not known. This significant real world population of TPMSs
suggests that TPMSs will continue to work with replacement tires in the
vast majority of cases.
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\28\ Letter from Robert Strassburger, Vice President, Alliance
of Automobile Manufacturers, to NHTSA (October 20, 2003) (Docket No.
NHTSA-2000-8572-277).
\29\ 67 FR 38704, 38731 (June 5, 2002).
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However, NHTSA has been presented with data demonstrating that a
very small number of replacement tires (estimated at less than 0.5
percent of production) may have construction characteristics and
material content that cause the vehicle's TPMS to exhibit functional
problems. There is no clear design solution for this problem. In many
instances, TPMSs may function properly even when equipped with
replacement tires with the previously discussed characteristics.
However, to date, it has not been possible to develop an appropriate
performance measure that would reliably identify those anomalous tires
that would prevent proper TPMS functioning.
Further, it is NHTSA's understanding that some of the reported
compatibility problems between direct TPMSs and certain replacement
tires may have been related to vehicle manufacturer use of TPMS
transmitters and receivers produced by different suppliers.\30\
Incompatibility between different parts of the TPMS may have
contributed to the overall problem in those cases. Thus, cognizance of
this problem may limit further the number of incidents of
incompatibility between TPMSs and replacement tires.
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\30\ GM submitted a letter to NHTSA on September 11, 2003,
outlining the problems that their direct TPMS was experiencing when
different run-flat tires were installed on the vehicle. (Docket No.
NHTSA-2000-8572-275) Subsequent discussions revealed that TPMS
components from different TPMS manufacturers were used and that the
same tires permitted proper TPMS functioning when TPMS components
from a single TPMS manufacturer were used.
---------------------------------------------------------------------------
Based upon the above new information, we now believe that there is
not a sufficient basis to require vehicles to comply with FMVSS No. 138
with all replacement tires. While the number of tires expected to be
incompatible with the TPMS is small, such a requirement would
nonetheless raise significant practicability concerns.
We continue to believe, however, that the TPMS should continue to
function properly beyond the point at which the vehicle's original
tires are replaced, a clearly foreseeable event. Continued TPMS
functionality with replacement tires is consistent with Congress's
intention to improve tire and vehicle safety, as expressed in the TREAD
Act. Moreover, there are other TPMS failure modes (e.g., pressure
sensor battery life, pressure sensor failure, antenna failure, TPMS
power loss), and unless drivers are made aware of such failures, they
could have a false sense of security. Therefore, in this NPRM, we are
proposing to require the TPMS to be equipped with a telltale indicator
that would alert the driver of a TPMS malfunction, tire-related or
otherwise. In addition, we are proposing owner's manual requirements to
make consumers aware of this potential problem. The details of these
proposed requirements immediately follow.
[[Page 55905]]
We believe that this approach offers a reasonable alternative that
would not only facilitate continued proper TPMS operation with
replacement tires, but also would provide the driver with valuable
information regarding malfunction of the TPMS.
a. TPMS Malfunction Indicator
In proposing to require a malfunction indicator, NHTSA sees an
opportunity not only to provide a means of warning when incompatible
replacement tires have been installed on the vehicle, but at the same
time also to provide the driver with notice when some other problem has
rendered the TPMS inoperative. We are proposing to require a TPMS
malfunction indicator that ``illuminates whenever there is a
malfunction that affects the generation or transmission of control or
response signals in the vehicle's tire pressure monitoring system.''
Examples of malfunctions that would trigger the TPMS malfunction
indicator include, but are not limited to, the following: (1) Loss of
power or insufficient power to the TPMS control unit; (2) loss of power
or insufficient power from one or more wheel sensors due to a low or
dead battery; (3) inadequate signal transmission from one or more TPMS
sensors, or (4) inadequate signal reception by the system's antenna/
receiver, attributable to a defective wheel sensor, a defective
antenna, or incompatible replacement tire.\31\ We believe that
operational details of when the malfunction indicator would be
triggered will depend upon the strengths and limitations of a given
TPMS. We request comment on whether our proposed requirement for
malfunction detection is sufficiently broad to detect and report TPMS
malfunctions, regardless of the type of system installed. We also
request comment on whether our proposed requirement is sufficiently
specific to enable manufacturers to know the types of malfunctions the
system must be capable of detecting and reporting. If not, we request
comments on how it should be made more specific.
---------------------------------------------------------------------------
\31\ We are not proposing to require the TPMS malfunction
indicator to illuminate when a spare tire without a TPMS transmitter
is used, because we believe that a consumer would not be lulled into
a false sense of security under that scenario.
---------------------------------------------------------------------------
Under the proposal, the malfunction indicator would not be required
to specify the cause of the malfunction. We have tentatively decided
not to establish such a requirement for several reasons. First, a
multiplicity of TPMS malfunction messages could confuse the consumer.
Second, there are obvious space limitations on the instrument panel or
reconfigurable display, space that might more prudently be reserved for
some other safety warning in the future. In addition, we believe that
for most consumers, correction of a TPMS malfunction will necessitate
vehicle servicing by a trained professional.
We believe that it is important that the message for TPMS
malfunction be distinct from the message for low tire pressure. We are
proposing to allow manufacturers to choose from two options \32\ for
the TPMS malfunction indicator to ensure that distinctness.
---------------------------------------------------------------------------
\32\ We note that, under either proposed option, it would be
permissible to incorporate the TPMS malfunction indicator as part of
a reconfigurable display, provided all proposed requirements are
met.
---------------------------------------------------------------------------
(1) Separate TPMS Malfunction Telltale
Under the first proposed option, a vehicle manufacturer would be
required to install a dedicated yellow telltale (pictured below) that
is separate from the low tire pressure warning indicator and that would
illuminate upon detection of a malfunction and remain continuously
illuminated as long as the malfunction exists, whenever the ignition
locking system is in the ``On'' (``Run'') position. It also would be
required to perform a bulb-check at vehicle start-up. This TPMS
malfunction telltale would be required to be labeled with the symbol
below, or that symbol and the word ``TPMS.''
[GRAPHIC] [TIFF OMITTED] TP16SE04.008
[[Page 55906]]
We are proposing yellow (as opposed to red) as the appropriate
color for the dedicated malfunction telltale because, in most cases,
malfunction of the TPMS would not constitute an imminent safety problem
necessitating immediate driver action. A vehicle's tires may be
properly inflated, even if the malfunction indicator is triggered.
Therefore, we believe that a yellow cautionary telltale would be
appropriate to indicate that while a problem with the TPMS exists, the
vehicle may be driven safely until the opportunity arises to have the
situation corrected.
We are proposing that, once triggered, this separate TPMS
malfunction indicator would be continuously illuminated as long as the
malfunction exists, whenever the ignition locking system is in the
``On'' (``Run'') position. We are making this proposal because the TPMS
is an important piece of safety equipment, and we believe that the
driver should be constantly reminded when such equipment is not
operating properly. The requirement for constant illumination is
consistent with the operation of other warning telltales.
After conducting an evaluation of possible icons, NHTSA selected
the proposed symbol for TPMS malfunction, which is based upon an
international ISO design used to signal low tire pressure. In selecting
the proposed symbol, we sought to choose an icon that could be
recognized by consumers, that would help achieve the desired response,
and that at the same time would be consistent with the ISO standard. If
the consumer were not already familiar with the telltale, the preferred
response would be to lead people to consult the owner's manual for
further information, rather than an extreme response (e.g., stopping
the vehicle immediately).
As in the case of the requirement for bulb checks for other
telltales, we believe that the proposed requirement for a bulb check
for the malfunction telltale would provide an important safety benefit
(i.e., ensuring that the telltale is capable of illuminating in order
to deliver its message) at minimal cost.
(2) Combination Low Tire Pressure/TPMS Malfunction Telltale
Under the second proposed option, a vehicle manufacturer could
incorporate the TPMS malfunction indicator function as part of the
required low tire pressure telltale. Proposed requirements for color,
wording, bulb check, and illumination format for the low tire pressure
function (all discussed elsewhere in this proposal), would be
unaffected by the incorporation of the TPMS malfunction indicator
within the same telltale.
In order to indicate a malfunction, the low tire pressure telltale
would be required to flash for a period of one minute, after which time
the telltale would remain continuously illuminated as long as the
malfunction exists and the ignition locking system is in the ``On''
(``Run'') position. We limited the period to one minute to avoid
distracting or bothering the driver. This flashing and illumination
sequence would be repeated upon subsequent vehicle start-ups until the
situation causing the malfunction has been corrected. We believe that
flashing the low tire pressure telltale to indicate TPMS malfunction is
a sufficiently distinct message to enable the driver to differentiate
between the two warnings; any confusion between the messages would be
resolved easily by consulting the owner's manual.
The agency is especially interested in comments related to the
specific details of the mode of operation of the proposed TPMS
malfunction indicators, as well as possible alternatives. We invite
views on the telltales' malfunction symbol(s) and how the signal is
presented to the driver, in order to assess its effectiveness in
delivering a clear message.
b. Owner's Manual Requirements Related to Replacement Tires and the
TPMS Malfunction Indicator
The second part of our proposed approach for addressing continued
operation of the TPMS with replacement tires involves requiring vehicle
manufacturers to provide relevant information to consumers in the
vehicle owner's manual. Generally, we are proposing to require language
to alert consumers regarding: (1) Potential problems related to
compatibility between the vehicle's TPMS and various types of
replacement tires, and (2) the presence and operation of the TPMS
malfunction indicator. For those vehicles without an owner's manual, we
are proposing to require that this information be supplied to the
purchaser in writing at the time of initial vehicle sale. We request
comments on our proposed owner's manual language, including any
suggestions for modifications and accompanying rationale.
Specifically, under paragraph S4.5 of the standard, we are
proposing to require the following language to be printed in the
vehicle's owner's manual:
Your vehicle has also been equipped with a TPMS malfunction
telltale to indicate when the system is not operating properly. When
the malfunction telltale is illuminated, the system may not be able
to detect or signal low tire pressure as intended. TPMS malfunctions
may occur for a variety of reasons, including the installation of
incompatible replacement tires on the vehicle. Always check the TPMS
malfunction telltale after replacing one or more tires on your
vehicle to ensure that the replacement tires are compatible with the
TPMS.
2. Spare Tires
In the June 5, 2002 final rule, we decided not to require the TPMS
to monitor the pressure in a spare tire (either compact or full-sized),
either while stowed or when installed on the vehicle (67 FR 38704,
38731). We came to this decision for a number of reasons, including the
knowledge on the part of drivers that temporary tires are not intended
for extended use, the fact that compact spare tires pose operational
problems for both direct and indirect TPMSs, the potential disincentive
for manufacturers to supply a full-size spare if TPMS compliance were
required, and the increased cost of the rule, with little if any safety
benefit, if a spare tire must be monitored. NHTSA stated that it would
not conduct compliance testing under Standard No. 138 with spare tires
installed on the vehicle.
The Alliance petition asked NHTSA to further clarify the final rule
to acknowledge that a properly calibrated TPMS will activate the TPMS
telltale after a small spare tire or a full-sized spare tire without a
pressure sensor is installed. According to the Alliance, in situations
in which a spare tire is in use, information regarding the inflation
pressure of the remaining three tires may or may not be indicated by
the TPMS, depending upon the type of system and display used. The
Alliance asked for an explicit statement that the standard does not
require a TPMS to indicate low pressure in any of the remaining three
tires when a spare tire is installed on a vehicle.
We acknowledge that in certain instances, use of a spare tire on a
vehicle may prevent the proper operation of the TPMS. However, we
believe that the Alliance's recommended regulatory language is
unnecessary, because the proposed language in paragraph S4.5, Written
Instructions, of the NPRM adequately addresses this issue. That
provision proposes to permit a vehicle manufacturer to include in the
vehicle owner's manual a statement of ``whether the tire pressure
monitoring system functions with the vehicle's spare tire (if
provided).'' This proposed language is sufficient to cover all aspects
of a
[[Page 55907]]
TPMS's capability to function when a spare tire is in use.
In addition, during the course of this rulemaking, GM suggested a
clarification in paragraph S4.5.1 of the standard, which deals with
TPMS-related written instructions in the vehicle owner's manual (see
Docket No. NHTSA-2000-8572-258 in the DOT Docket Management System Web
site at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://dms.dot.gov). Specifically, GM noted that vehicle
manufacturers are not required to provide a spare tire, and some
vehicles do not come equipped with spare tires. Consequently, GM
suggested that the standard be amended to reflect this possibility,
thereby preventing consumer confusion.
We agree with GM that not all vehicles are equipped with spare
tires and that consumers might be confused to see language in the
owner's manual, as contained in the June 2002 final rule, for a vehicle
that is not equipped with a spare tire. Accordingly, in the NPRM, we
have drafted proposed paragraph S4.5 to reflect the potential absence
of a spare tire.\33\
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\33\ NHTSA has eliminated the owner's manual requirement
contained in S4.5.2, due to the Second Circuit's invalidation of the
underlying one-tire, 30-percent option. Accordingly, as part of this
proposal, we have consolidated the remaining owner's manual
requirements under S4.5 and included the change related to spare
tires in that section.
---------------------------------------------------------------------------
3. Low Tire Pressure Telltale
Paragraph S4.3 of FMVSS No. 138 required that each vehicle be
equipped with a yellow telltale that is mounted in plain view of the
driver and is identified by the symbols and phrases specified for low
tire pressure in S5.2.3 and Table 2 of FMVSS No. 101, Controls and
Displays.\34\ It also stated the conditions under which the TPMS
telltale must illuminate and the conditions under which the TPMS must
extinguish or deactivate the telltale.
---------------------------------------------------------------------------
\34\ We note that if a vehicle manufacturer elects to install a
low tire pressure telltale that indicates which tire is under-
inflated, the telltale must correctly identify the under-inflated
tire. See S4.3.2.
---------------------------------------------------------------------------
Specifically, the TPMS telltale was required to be illuminated
continuously when low tire pressure is detected under the parameters
set forth in S4.2 of FMVSS No. 138. In addition, it was required to be
illuminated as a bulb check when the ignition locking system is in the
``on'' position and the engine is not operating, or when the ignition
locking system is in a position between ``on'' and ``start'' that is
designated by the manufacturer as a check position. Paragraph S6(j) of
the standard provided a test procedure, in which the TPMS telltale is
to be extinguished automatically, although it does not specify a time
limit for the telltale to be turned off.
A number of the petitioners raised issues about the TPMS warning
telltale requirements, including issues related to permissible color,
use of reconfigurable displays, extinguishment time, bulb check, and
indication of TPMS malfunction. A discrepancy also was identified
between FMVSS No. 138 S4.3.1(b) and FMVSS No. 101 S5.2.3 and Table 2.
Each of these issues will be discussed in turn. (Please note that all
relevant telltale issues related to the newly proposed TPMS malfunction
indicator are discussed above in Section III.C.1 (Replacement Tires).)
Color
Petitions submitted by Volkswagen, the Alliance, and BNA's ISO/TC22
all raised issues related to TPMS telltale color. The petition of BNA's
ISO/TC22 recommended replacement of the yellow TPMS telltale required
under the June 5, 2002 final rule with a red lamp, arguing that
illumination of the TPMS telltale should be treated as an alert to the
driver to check the tire pressure and to take corrective action
immediately. The petitioner reasoned that the TPMS should have a red
telltale, consistent with other failure telltales, rather than a yellow
``warning'' telltale, which does not connote a need for immediate
corrective action. It was mentioned that ISO, an international
standard-setting body, is currently preparing a new standard for ``Tyre
Pressure Monitoring Systems,'' which can be expected to have a
requirement for a red telltale.\35\
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\35\ NHTSA understands that ISO had made plans to convene a
meeting in April 2004, in order to obtain agreement on performance
specifications and test procedures for a ``Tyre Pressure Monitoring
Systems'' standard, with the intention of presenting a draft
document to its members for balloting in June 2004. A date for
issuance of a final ISO standard has not been set.
---------------------------------------------------------------------------
Volkswagen's petition also asked the agency to modify its
requirement in FMVSS No. 101 for the color of the TPMS telltale.
However, Volkswagen seeks to have the standard permit a dual-color TPMS
telltale, which would switch from yellow to red when tire pressure
falls below a specified level deemed to be dangerously low. The
petitioner acknowledged the possibility that such TPMS telltales may
display as red immediately if air loss is sufficiently rapid or is
below a safe driving level upon start-up. However, Volkswagen believes
that a TPMS telltale with dual yellow/red illumination capabilities
would provide an enhanced level of warning to drivers in urgent
situations and notes that such TPMS telltales are currently in use on
some vehicles.
Volkswagen also asked that the final rule be modified to permit the
use of a white lamp in the event the TPMS telltale is permitted to be
part of a reconfigurable (multi-function) display. In line with its
recommendations, Volkswagen's petition asked the agency to require
vehicle owner's manuals to explain the functional meaning of the colors
utilized for the TPMS telltale.
The Alliance believes that the final rule's specified requirements
for telltale color are unnecessarily design-restrictive. Its petition
also recommended amendment of the standard to permit both the yellow/
red TPMS telltale color combination and the white TPMS telltale for
reconfigurable displays.
We continue to believe that yellow is the most appropriate color
for the low tire pressure telltale, consistent with the reasoning set
forth in the final rule, so in this NPRM, we are again proposing a
yellow telltale requirement as part of the standard. We will briefly
restate our reasoning. The use of the color red usually is reserved for
telltales warning of an imminent safety hazard. An example is the brake
system warning telltale, which is red because a failure in a vehicle's
brake system results in an imminent safety hazard that requires
immediate attention. In contrast, NHTSA requires a yellow telltale for
driver warnings when the safety consequences of the malfunctioning
system do not constitute an emergency and the vehicle does not require
immediate servicing.
Tire pressure monitoring systems are designed to detect a
relatively slow loss of tire pressure so that the driver can seek the
necessary tire maintenance and prevent a major tire failure that could
result in catastrophic consequences (i.e., the type of situation where
a red telltale would be suitable). Based upon the agency's testing of
tires at 20 pounds per square inch (psi) (the minimum activation
pressure for the TPMS telltale), we do not believe that a significantly
under-inflated tire represents an imminent safety hazard, particularly
because we are proposing a requirement for under-inflation detection
and warning at a point when the vehicle may still be operated safely.
If we were to require a red telltale, we would be conveying a very
different message regarding the urgency of the low tire pressure
situation and the action to be taken (i.e., the need for an immediate
stop). If we were to permit a telltale that changes color from yellow
to red, we are concerned that this could confuse consumers,
particularly if it is left to the discretion of individual vehicle
manufacturers to decide the
[[Page 55908]]
level of under-inflation at which the red telltale is triggered.
Conceivably, a manufacturer could program the TPMS to illuminate a
yellow telltale for a fraction of a second, after which time it would
immediately turn red; such a result would meet the letter of the
requirement, but foil its intent. Accordingly, we stand by our
conclusion that yellow is the appropriate color for the low tire
pressure telltale because it conveys the message that the driver may
continue driving, but should check and adjust the tire pressure at the
earliest opportunity.
Although we are proposing to retain the yellow color requirement
for the low tire pressure telltale in this NPRM, it has traditionally
been our practice to permit manufacturers to take additional measures,
consistent with Federal motor vehicle safety standards, that are
designed to further enhance safety. Consequently, we are proposing to
permit manufacturers to incorporate a second, red light to accompany
the continuously-illuminated yellow TPMS telltale, which would be
illuminated when pressure in one or more tires becomes dangerously
under-inflated, as determined by the manufacturer. If a manufacturer
chooses to add a second, red warning light, its meaning and function
would have to be discussed in the vehicle's owner's manual.
NHTSA has not adopted the recommendation that the agency waive the
yellow color requirement to also permit a white color for TPMS
telltales that are part of a reconfigurable display. We believe that
color imparts meaning in the context of warning telltales, and the
petitioners have provided insufficient data to justify exempting TPMS
telltales in reconfigurable displays from being subject to the
standard's proposed yellow color requirement.
Reconfigurable Display
The petitions for reconsideration submitted by Johnson Controls,
Volkswagen, and the Alliance all raised concerns related to the
permissibility of incorporating the TPMS telltale in reconfigurable,
multi-function displays. Reconfigurable displays utilize a common space
to provide a variety of information to the driver; typically, these
displays have a screen on which different messages may occupy the same
position at different times.
While acknowledging the agency's concerns regarding the safety
implications of permitting a vehicle operator to deactivate the TPMS
telltale or reconfigure the display so that the TPMS telltale is not
visible, the Johnson Controls petition stated that reconfigurable
displays can be designed to meet the requirements of the June 5, 2002
final rule. Specifically, a reconfigurable telltale could be produced
that automatically illuminates and remains continuously illuminated
while one or more tires are significantly under-inflated and that is
extinguished only when the tires cease to be significantly under-
inflated. (We assume that other messages that normally share the same
position on the reconfigurable display as the TPMS telltale either
would be suppressed or migrate to a different position on the display.)
Johnson Controls asked the agency to clarify the TPMS rule to
acknowledge that the TPMS telltale may be part of a reconfigurable
display, provided that the above two conditions are met. The petitioner
noted that this clarification would not require any substantive change
to the TPMS standard, but it would allow manufacturers to continue to
have the option of utilizing multi-function display technology while
fully complying with the requirements of the regulation.
Volkswagen's petition argued that the final rule's telltale
requirements are too design restrictive and requested that the TPMS
telltale be permitted as part of a reconfigurable display that
illuminates the TPMS telltale when the vehicle is shifted into a
forward driving gear and which displays the telltale on an
interruptible but persistent basis until the tire pressure is corrected
or until the system is reset manually in accordance with the vehicle
manufacturer's instructions.
In the interest of safety, we incorporated a requirement in the
June 5, 2002 final rule for continuous illumination of the TPMS
telltale as long as one or more of a vehicle's tires is significantly
under-inflated. While the TPMS rule did not explicitly prohibit the
incorporation of the TPMS telltale into a reconfigurable display, we
questioned the ability of a reconfigurable display to meet the
requirements of S4.2 of the standard, due to the constant illumination
requirement. In drafting the June 2002 final rule, we were concerned
also that a vehicle operator may be able to reconfigure the display in
such a way that the important safety message provided by the TPMS
telltale is no longer visible, which is not acceptable.
In the current proposal, FMVSS No. 138 once again would not
prohibit outright the inclusion of the TPMS telltale as part of a
reconfigurable display, and we note Johnson Controls' statement that
reconfigurable displays currently exist which can meet the proposed
requirements of the standard, including the provision for continuous
illumination. Thus, we want to make it clear that we are proposing that
it would be permissible to incorporate the TPMS telltale as part of a
reconfigurable display, provided that illumination of the yellow
telltale is continuous while one or more tires is under-inflated.
However, we want to emphasize that under this proposal, the TPMS
telltale would not be permitted to flash or cycle when performing its
under-inflation detection function. Further, the display could not be
controlled by the driver so as to disable the TPMS safety message prior
to remedying the low pressure condition, including by scrolling the
message down such that it is no longer visible. Thus, reconfigurable
displays that provide a persistent, but cycling, TPMS warning would not
meet the standard's proposed requirement for continuous illumination.
Extinguishment Time
The Johnson Controls petition asked the agency to amend the June
2002 final rule to specify a timing requirement for TPMS telltale
extinguishment, in cases in which the tire pressure deficiency has been
corrected and there is no manual reset feature. In recommending a
timeframe for extinguishment, the petitioner stated that because both
illumination and extinguishment of the telltale involve the same
detection considerations from a technological standpoint,
extinguishment should occur within ten minutes. Accordingly, Johnson
Controls petitioned NHTSA to amend the testing procedures in FMVSS No.
138 S6(j) of the June 5, 2002 final rule to provide that unless there
is a manual reset feature, the manufacturer must record the time to
extinguishment after the vehicle reaches 50 km/hr and that the TPMS
telltale must extinguish within ten minutes. The petitioner also asked
that the testing procedures in FMVSS No. 138 S6(i) be amended to
require verification of telltale extinguishment if the TPMS system has
a manual reset feature.
We are not adopting the suggestion of Johnson Controls to require a
time limit for TPMS telltale extinguishment. Telltale extinguishment is
addressed already under FMVSS No. 101. Specifically, paragraph S5.3.1
of FMVSS No. 101 provides, ``A telltale shall not emit light except
when identifying the malfunction or vehicle condition for whose
indication it is designed or during a bulb check upon vehicle
starting.'' The TPMS telltale is not excluded from this requirement.
NHTSA has not imposed specific time limits for extinguishment of
other telltales, and given the existing
[[Page 55909]]
requirements of FMVSS No. 101, we do not believe it is necessary to do
so for the TPMS telltale at this time, although we acknowledge that
TPMS technology may require a certain period of time to detect that the
low-pressure situation has been corrected before extinguishing the
telltale.
Bulb Check
Paragraph S4.3.3 of the June 5, 2002 final rule provided that the
TPMS warning telltale must be activated as a check of lamp function
either when the ignition locking system is turned to the ``On''
(``Run'') position when the engine is not running, or when the ignition
locking system is in a position between ``On'' (``Run'') and ``Start''
that is designated by the manufacturer as a check position. However,
the telltale need not be activated when a starter interlock is in
operation.
The petitions of both Volkswagen and the Alliance recommended
changes to the June 2002 final rule's requirements related to a bulb
check for the TPMS telltale. Volkswagen expressed agreement with the
Alliance's recommendation in its comments on the earlier NPRM that a
bulb check function should not be required because manufacturers
routinely include serviceability provisions as a normal design
practice, thereby rendering that regulatory provision unnecessary.
Volkswagen also stated that if the TPMS telltale were permitted as part
of a multi-functional display, the telltale would not necessarily
illuminate because internal vehicle diagnostics monitor the system, and
illumination of the display itself constitutes the bulb check function.
Consequently, Volkswagen asked NHTSA to eliminate the requirement for
the bulb check function. Alternatively, Volkswagen asked the agency to
amend S4.3.3(a) to clarify that the bulb check function does not apply
if the TPMS telltale is part of a reconfigurable display.
We are proposing to retain a requirement for a bulb check for the
TPMS low tire pressure telltale as part of this NPRM, because a bulb
check helps ensure the functionality of the TPMS warning system in a
consistent and uniform fashion. The safety benefits associated with the
TPMS will only be realized if the TPMS telltale can illuminate so as to
provide the requisite warning to the vehicle operator. Consequently,
NHTSA continues to believe that a bulb check will provide vehicle
operators with useful information (i.e., that the warning telltale bulb
is functional), and these benefits will come at little, if any,
additional cost. (This same reasoning applies to the bulb check for the
proposed dedicated TPMS malfunction telltale, if the vehicle is so
equipped.)
For the safety-related reasons discussed above, we believe that the
proposed bulb check requirement also should apply when the TPMS
telltale is part of a reconfigurable display. However, we are proposing
that illumination of the reconfigurable display itself would constitute
a sufficient bulb check under the standard, as long as the low tire
pressure telltale is one of the displays activated.
Harmonization of FMVSS 138 S4.3.1(b) and FMVSS 101 Table 2
The petitions of Johnson Controls and the Alliance asked NHTSA to
resolve an apparent discrepancy under the June 5, 2002 final rule
between S4.3.1(b) of FMVSS No. 138 and S5.2.3 and Table 2 of FMVSS No.
101. These provisions discussed the permissible use of words and
symbols as part of the TPMS telltale. As the petitioners point out,
FMVSS No. 101 S5.2.3 stated that for a TPMS telltale that does not
identify which tire has low pressure, the TPMS telltale may include the
symbol in Table 2 or the symbol and the words ``Low Tire.'' That same
provision provided that for a TPMS telltale that does indicate which of
the four tires is experiencing low pressure, the telltale may either
use the symbol or the words indicated in Table 2. However, FMVSS No.
138 S4.3.1(b) stated that the TPMS telltale must be identified by one
of the symbols shown for the low tire pressure telltale in Table 2 of
Standard No. 101. Consequently, the petitioners contended that these
two provisions are unclear as to the content requirements for the TPMS
telltale for systems that identify which tire has low pressure.
The two petitions, however, recommended different remedies. Johnson
Controls recommended resolving the discrepancy by modifying FMVSS No.
138 S4.3.1(b) so as to remove the language ``one of the symbols shown
for the 'Low Tire Pressure Telltale' in Table 2'' and replace that
phrase with ``a telltale permitted by Section 5.2.3.'' The Alliance
recommended modifying FMVSS No. 101 S5.2.3 so as to eliminate the two
parenthetical phrases stating ``(that does not identify which tire has
low pressure).'' Elimination of that phrase would have the effect of
requiring either a symbol from Table 2 or both a symbol and words from
Table 2.
We agree with the petitioners that the identified provisions in
FMVSS No. 101 and FMVSS No. 138 must be reconciled in order to denote
clearly what constitutes a permissible TPMS telltale and thus have
addressed this issue in the NPRM. The preamble to the June 2002 final
rule made clear the agency's intent regarding the visual content of the
TPMS telltale for those systems that identify which tire has low
pressure. Specifically, the preamble stated, ``Thus, the final rule
requires the use of this image, with lamps at the image's tires to
indicate which tire is significantly under-inflated, if a vehicle
manufacturer provides a display that identifies which tire is
significantly under-inflated.'' 67 FR 38704, 38732. Without the symbol,
the words ``Low Tire'' would not indicate which of the vehicle's four
tires had low pressure.
In order to resolve the discrepancy, as part of this NPRM, we are
proposing to adopt the recommended solution put forth by the Alliance
and rejecting the solution suggested by Johnson Controls. The
recommended solution in the Johnson Controls petition would permit a
manufacturer to choose a telltale displaying the words ``Low Tire''
without a symbol. Not only would such an outcome be at odds with the
agency's clear intent articulated in the June 2002 final rule's
preamble, but it would also be an inappropriate result for a TPMS
designed to ``identify which tire has low pressure.'' Accordingly, as
part of this NPRM, we are proposing that FMVSS No. 101 S5.2.3 require a
TPMS symbol in all cases, with optional supplementation by the words
``Low Tire.''
Indication of TPMS Malfunction
The Alliance petition requested that NHTSA modify the June 2002
final rule specifically to allow the TPMS telltale to alert the vehicle
operator in the event of a TPMS system malfunction. The Alliance argued
that the agency has permitted other required telltales to flash to
indicate malfunctioning systems, but it also noted that the preamble
and the regulatory text of FMVSS No. 138 S4.2.1 and S4.2.2 required
constant illumination once the telltale is triggered until the low-
pressure situation is resolved. To indicate TPMS system malfunction,
the Alliance recommended permitting the telltale to flash, as distinct
from a steady activation pattern indicating low tire pressure, and it
asked the agency to amend paragraphs S4.2, S4.3, and S4.5 of FMVSS No.
138 accordingly.
Consistent with our proposed resolution of the replacement tire
issue, NHTSA is proposing to require the TPMS to include a TPMS
malfunction indicator. Details of the proposed requirements for the
TPMS malfunction
[[Page 55910]]
indicator and related matters are fully discussed under Section III.C.1
(Replacement Tires) above.
4. Test Procedures
A number of petitions raised issues about testing procedures under
the June 2002 final TPMS rule, including petitions submitted by Delphi,
DENSO, Volkswagen, and the Alliance. Concerns were raised regarding
what petitioners perceived to be inadequate specificity and objectivity
of those test procedures. Specifically, petitioners raised issues
related to rim position, calibration, test specificity, and reset, each
of which will be addressed in further detail below. In addition,
DENSO's petition asked the agency to issue a TPMS Compliance Test
Procedure on an expedited basis, because DENSO stated that
manufacturers will need sufficient lead time (e.g., DENSO estimated one
year) to implement the TPMS design specifications and to begin
installation of TPMSs in new vehicles.
Petitioners argued that in light of the capabilities of TPMS
systems, specific test procedures are necessary. While we do not agree
with all of the petitioners' contentions, in order to ensure
objectivity, we are proposing to identify a specific test course and to
incorporate it in the standard as part of this NPRM. This proposed
course is the Southern Loop of the Treadwear Course, as defined in
Appendix A and Figure 2 of 49 CFR 575.104, which is located on various
highways in and around San Angelo, Texas. We propose that testing would
be conducted starting at any point on the course.
We see several benefits to this approach, foremost of which is that
this test course could be incorporated into the standard in a timely
fashion. It would not be necessary to design or build a new test track
for compliance testing purposes or to conduct extensive research to
describe such a test course.
Further, the proposed course is well known and has been used for
decades by NHTSA and the tire industry for uniform tire quality grading
(UTQG) testing. Testing on a section of public highway would help to
ensure that any required TPMS calibration will be performed
appropriately and that low tire pressure detection would be evaluated
appropriately during testing. Also, vehicle manufacturers would be able
to review the course and to use it to verify compliance of their TPMS
prior to vehicle certification. Thus, by proposing to require vehicles
to satisfy the TPMS requirement when tested at any portion of this
course, TPMSs would be designed to operate properly on a variety of
roadways and conditions, and the standard would satisfy the requirement
of objectivity.
Designation of a specific test course in and around San Angelo
could pose some potential problems if that section of highway were to
experience closures related to major road repairs or damage due to
extreme weather conditions or natural disasters. However, we believe
that the probability of such occurrences is very small, particularly to
the extent that the entire test course would be unavailable. Because
the proposed test course is approximately 140 miles in length, if one
portion were to become unavailable, testing could be conducted on a
different segment of the course. Again, we note that this particular
test course has been used successfully for UTQG testing purposes for a
number of years, and we believe that it would be suitable for TPMS
testing as well.
Additional details are provided below regarding proposed changes to
the standard's test conditions and procedures that reflect differences
between the June 5, 2002 final rule and this NPRM.
Rim Position
Under the June 5, 2002 final rule, paragraph S6(l) of the standard
stated that the original rims are to be used with any replacement tires
recommended by the manufacturer (that are of a suitable size to fit the
OE rims; otherwise, appropriately sized OE rims will be used).
The petition for reconsideration filed by Johnson Controls asked
the agency to revise the test procedures in paragraph S6(l) to specify
that the original rim position (i.e., left front, left rear, right
front, right rear) will be preserved when replacement tires are placed
on the vehicle. According to the petition, such positioning is
important to preserve the integrity of the original training of the
TPMS. Johnson Controls stated that most direct TPMSs require that the
system initially be trained to recognize the transmitters on the rims
and their relative positions on the vehicle, with such training
routinely occurring during vehicle assembly. This change was
recommended to prevent compliance testing in a manner that would foil
the proper functioning of the TPMS.
We anticipate that there will be many instances in which consumers
and vehicle repair/service technicians will not maintain original rim
position, either intentionally or unintentionally. As a primary
example, many vehicle manufacturers direct owners to rotate their tires
on a regular basis, based on time, mileage, or both. Maintaining
original rim position during tire rotation would necessitate the
additional time and expense of removing each tire from its wheel rim
prior to rotation, rather than simply shifting the entire wheel and
tire assembly, which is the normal way tires are rotated. Moreover,
contrary to the implication of the Johnson Controls petition, some
manufacturers of vehicles with a direct TPMS provide instructions in
the owner's manual regarding how to reprogram the TPMS sensors
following wheel rotation (see, e.g., the TPM sensor identification
codes section of the MY 2004 GMC Yukon owner's manual, at page 5-74).
However, after considering the Johnson Controls petition, we have
drafted a new paragraph S5.3.3, Rim position, in the NPRM to provide
that we would maintain the original rim positions when conducting
compliance testing in those cases in which the vehicle manufacturer
directs owners to retain the original rim positions in the owner's
manual. We would also follow any instructions contained in the vehicle
owner's manual related to tire rotation and rim position, regardless of
whether such instructions are included in a discussion of the TPMS or
in some other portion of the owner's manual. If a vehicle manufacturer
does not make such rim position recommendations, the agency would be
free to mount the rims in any position on the vehicle when conducting
compliance testing. (If the tires and rims on the front and rear axles
were not the same size, the tires and rims would remain on the
appropriate axle. We would ensure also that unidirectional tires are
mounted appropriately.\36\) Before conducting such compliance tests,
the agency would follow all manufacturer recommendations with respect
to reprogramming the TPMS to account for changes in rim positions.
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\36\ Unidirectional tires are tires that are designed to rotate
in one specified direction during forward motion. This directional
limitation is primariliy based upon tread pattern design.
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Calibration
As part of the June 2002 final rule's test procedures, paragraph
S6(d) specified that the vehicle be driven at any speed between 50 km/
hr and 100 km/hr for 20 minutes prior to conducting the TPMS low
inflation pressure detection test. This procedure was designed to
calibrate or to establish a baseline for the TPMS. As noted in the June
5, 2002 final rule, indirect TPMSs need time to calibrate the system
under certain circumstances, such as when a vehicle is driven for the
first time (i.e., when it is new), when pressure in a tire is changed,
and when the tires are replaced or rotated. 67 FR 38704, 38730.
[[Page 55911]]
Until the system is properly calibrated, the TPMS may not be available
to monitor the vehicle's tire inflation pressure fully.
The petitions submitted by both Volkswagen and the Alliance raised
issues involving TPMS calibration and related test procedures. The two
petitioners argued that the test procedures in paragraph S6(d) do not
include sufficient detail and are design restrictive.
Volkswagen's petition sought clarification that TPMS calibration is
necessary when any one of the above-discussed three conditions occurs.
We acknowledge that calibration (or recalibration) of an indirect TPMS
may be necessary when any one of the above-stated conditions occurs.
Beyond this statement of clarification, we have also drafted this NPRM
so as to further accommodate the need for TPMS calibration, as
discussed below. These proposed changes include designation of a
specific test course and the inclusion of an expanded test procedure
for the ``system calibration/learning phase'' (S6(d)). We believe that
these measures would address the issues raised by the petitioner
regarding calibration.
Volkswagen's petition also asked the agency to modify the test
procedures in paragraph S6(d), which are designed to provide sufficient
initial driving time for indirect TPMSs to properly calibrate. Again,
that provision specified that the vehicle be driven for 20 minutes at
any speed specified in paragraph S5.3.2 (i.e., between 50 km/h (31.1
mph) and 100 km/h (62.2 mph)). However, Volkswagen argued that
paragraph S6(d) is not sufficiently specific to simulate the reasonable
and common driving conditions necessary for calibration of the TPMS.
Volkswagen asserted that for proper calibration of the TPMS, the
vehicle must be driven at least a minimal amount of time in various
speed ranges and within limits of forward and lateral acceleration.
According to Volkswagen, driving for calibration purposes should be on
reasonably straight roads, at controlled and reasonable speeds in the
turns, and with limited and moderated acceleration and braking.
Consequently, Volkswagen asked NHTSA to amend S6(d) to include a
statement that the vehicle shall be driven in accordance with the
manufacturer's specification. The Volkswagen petition stated that this
change would be consistent with the procedure in other standards in
which the vehicle manufacturer specifies test parameters, such as those
for fuel tank capacity, seat back angle and vehicle seat track
position, and vehicle weight.
The Alliance petition also supported greater specificity in the
TPMS test procedures, including paragraph S6(d). The petitioner argued
that those test procedures are overly design-restrictive and may hamper
development and performance of indirect TPMSs. The Alliance provided a
detailed discussion of the various TPMS algorithms and the
corresponding relationship between the complexity, capabilities, and
timing requirements of such algorithms. The Alliance asked the agency
to substitute a calibration procedure specified by the manufacturer in
the specified range of test speeds from 50 to 100 km/hr.
Although the Second Circuit's decision likely will lead to
increased use of direct TPMSs in the near term, NHTSA has decided to
address the calibration issue in any event, in anticipation of the use
of indirect TPMSs (or other systems for which calibration issues may be
important) that can meet the requirements of the standard. Because
NHTSA strives for standards that are technology-neutral, issues raised
in the petitions for reconsideration related to test procedures,
including but not limited to calibration, remain ripe for resolution.
While NHTSA acknowledges that the performance of an indirect TPMS
may be sensitive to road conditions and vehicle operating conditions,
it is important to ensure that each TPMS performs its intended function
during normal driving by the public. The purpose of paragraph S6(d) of
the TPMS test procedure, under both the June 5, 2002 final rule and
this NPRM, is to provide an opportunity for the vehicle to learn the
variables associated with distinct tire types under varying conditions.
Thus, we reject the suggestion that NHTSA be required to conduct its
compliance testing in accordance with the manufacturer's
specifications. That would allow a manufacturer to design a TPMS that
would function only in very limited circumstances, as opposed to the
wide variety of circumstances found in real-world driving.
We also believe that it is necessary to specify some objective
limit on calibration time for the following reasons. First, if the
calibration period is excessively long (e.g., several hours), there is
an increased chance that the vehicle could develop a serious leak
leading to significant tire under-inflation for which the TPMS would
provide no warning. Second, the public is likely to expect that, after
they follow the reset instructions in the vehicle owner's manual, the
TPMS will function as intended within a brief period of time. Further,
TPMS manufacturers have stated that their systems can properly
calibrate within 20 minutes, which demonstrates that such a timeframe
is practicable.\37\
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\37\ See e.g., Docket No. NHTSA-2000-8572-259.
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In order to ensure that our test procedures for calibration reflect
normal driving situations and to ensure objectivity, i