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NHTSA Interpretation File Search

Overview

NHTSA's Chief Counsel interprets the statutes that the agency administers and the standards and regulations that it issues. Members of the public may submit requests for interpretation, and the Chief Counsel will respond with a letter of interpretation. These interpretation letters look at the particular facts presented in the question and explain the agency’s opinion on how the law applies given those facts. These letters of interpretation are guidance documents. They do not have the force and effect of law and are not meant to bind the public in any way. They are intended only to provide information to the public regarding existing requirements under the law or agency policies. 

Understanding NHTSA’s Online Interpretation Files

NHTSA makes its letters of interpretation available to the public on this webpage. 

An interpretation letter represents the opinion of the Chief Counsel based on the facts of individual cases at the time the letter was written. While these letters may be helpful in determining how the agency might answer a question that another person has if that question is similar to a previously considered question, do not assume that a prior interpretation will necessarily apply to your situation.

  • Your facts may be sufficiently different from those presented in prior interpretations, such that the agency's answer to you might be different from the answer in the prior interpretation letter;
  • Your situation may be completely new to the agency and not addressed in an existing interpretation letter;
  • The agency's safety standards or regulations may have changed since the prior interpretation letter was written so that the agency's prior interpretation no longer applies; or
  • Some combination of the above, or other, factors.

Searching NHTSA’s Online Interpretation Files

Before beginning a search, it’s important to understand how this online search works. Below we provide some examples of searches you can run. In some cases, the search results may include words similar to what you searched because it utilizes a fuzzy search algorithm.

Single word search

 Example: car
 Result: Any document containing that word.

Multiple word search

 Example: car seat requirements
 Result: Any document containing any of these words.

Connector word search

 Example: car AND seat AND requirements
 Result: Any document containing all of these words.

 Note: Search operators such as AND or OR must be in all capital letters.

Phrase in double quotes

 Example: "headlamp function"
 Result: Any document with that phrase.

Conjunctive search

Example: functionally AND minima
Result: Any document with both of those words.

Wildcard

Example: headl*
Result: Any document with a word beginning with those letters (e.g., headlamp, headlight, headlamps).

Example: no*compl*
Result: Any document beginning with the letters “no” followed by the letters “compl” (e.g., noncompliance, non-complying).

Not

Example: headlamp NOT crash
Result: Any document containing the word “headlamp” and not the word “crash.”

Complex searches

You can combine search operators to write more targeted searches.

Note: The database does not currently support phrase searches with wildcards (e.g., “make* inoperative”). 

Example: Headl* AND (supplement* OR auxiliary OR impair*)
Result: Any document containing words that are variants of “headlamp” (headlamp, headlights, etc.) and also containing a variant of “supplement” (supplement, supplemental, etc.) or “impair” (impair, impairment, etc.) or the word “auxiliary.”

Search Tool

NHTSA's Interpretation Files Search



Displaying 15021 - 15030 of 16490
Interpretations Date

ID: 86-3.13

Open

TYPE: INTERPRETATION-NHTSA

DATE: 05/06/86

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: W.L. Hammer, P.E. -- Equipment Engineer, Wisconsin Electric Power Company

TITLE: FMVSS INTERPRETATION

TEXT:

Mr. W.L. Hammer, P.E. Equipment Engineer Wisconsin Electric Power Company 620 S. 76th Street Milwaukee, WI 53214

This is in reply to your letter of January 29, 1986, asking for an interpretation of the stop lamp and turn signal requirements of Federal Motor Vehicle Safety Standard No. 108.

Your first question is whether paragraphs S4.1.1.6 and S4.1.1.7 apply to vehicles manufactured in 1986. No. They apply to original equipment stop lamps on vehicles manufactured between January 1, 1973 and September 1, 1978 (S4.1.1.6), and to original equipment turn signal lamps on vehicles other than motorcycles manufactured between January 1, 1972, and September 1, 1978 (S4.1.1.7). However, they also apply to stop lamps and turn signal lamps manufactured after September 1, 1978, which are intended as replacement equipment for the original equipment manufactured between the inclusive dates. This is not exactly clear from a reading of the two paragraphs and we are considering a clarifying amendment to the standard. In summary, these paragraphs do not apply to vehicles manufactured in 1986, but they could apply to certain lighting equipment being manufactured today.

You also comment that S4.1.1.6 is silent as to the minimum luminous lens area required for stop lamps on vehicles whose overall width is 80 inches or more, which you recall as once being 12 square inches, and you ask if a final sentence has been omitted pertaining to wide vehicles. There has been no omission: SAE Standard J586b Stop Lamps, June 1966, the standard referenced in S4.1.1.6, never specified a minimum effective projected luminous lens area for wide vehicles. The requirement for wide vehicles today is found in paragraph 3.2 of SAE Standard J586c Stop Lamps, August 1970. This establishes a minimum effective projected luminous lens area of 8 square inches for single compartment lamps. However, paragraph 3.1 allows manufacturers of wide vehicles to mount a maximum of two lamps and/or compartments per side closer together than 22 inches providing that each compartment and/or lamp meets single compartment photometric requirements and has a minimum effective projected luminous lens area of 12 square inches.

I hope that this answers your questions.

Sincerely,

Original Signed By

Erika Z. Jones

Chief Counsel

January 29, 1986 National Highway Traffic Safety Administration 400 Seventh Street SW Washington, D.C. 20590

Gentlemen:

SUBJECT: 49CFR571.108 PARAGRAPH 4.1.1.6 STOPLIGHTS PARAGRAPH 4.1.1.7 TURN SIGNALS

I have been reading 571.108 as published in the 1984 edition of the Code of Federal Regulations. At first glance, Paragraphs 4.1.1.6 and 4.1.1.7 appear to only pertain to certain vehicles manufactured between 1972 and 1978 and not to those made before or after those dates. On a second glance, these paragraphs refer to a design option to meet SAEJ586b or 588d, or to meet SAEJ575d. Do these paragraphs apply to vehicles manufactured in 1986;

Also, in the case of Paragraph 4.1.1.6, a 3.5 square inch rule pertains to vehicles less than 80 inches in width, but there is no comment made for those vehicles over 80 inches in width. (I seem to remember it once was 12 square inches). Has a last sentence pertaining to vehicles over 80 inches been omitted:

A written reply is not required. A phone call would be satisfactory.

Sincerely,

W. L. Hammer, P.E. Equipment Engineer (414) 259-4152

ID: 22222.jeg

Open



    Mr. Andrew P. Doornaert
    Arthur Andersen LLP
    Suite 2700
    500 Woodward Avenue
    Detroit, MI 48226-3424



    Dear Mr. Doornaert:

    This responds to your letter requesting an interpretation of Part 583, Automobile Parts Content Labeling. You asked for clarification concerning how the value of certain "minor items" is treated in making various content calculations. Your questions are addressed below.

    You first asked about 583.6, Procedure for determining U.S./Canadian parts content. Paragraph 583.6(c)(4)(iv) of this section provides that "(f)or the minor items listed in the 583.4 definition of 'passenger motor vehicle equipment' as being excluded from that term, outside and allied suppliers may, to the extent that they incorporate such items into their equipment, treat the cost of the minor items as value added in the country of assembly." You noted that, as a result of a recent amendment to Part 583, the list of minor items once included in 583.4 is no longer there. However, the same list now appears in 583.6(a). The list is comprised of the following items: nuts, bolts, clips, screws, pins, braces, gasoline, oil, blackout, phosphate rinse, windshield washer fluid, fasteners, tire assembly fluid, rivets, adhesives, grommets, and wheel weights.

    You are correct that we did not intend to change the provision permitting outside and allied suppliers to treat the cost of these minor items as value added in the country of assembly. We plan in the future to issue a technical amendment to correct this now-obsolete cross-reference.

    You also asked whether the minor items provision of 583.6 can be considered in determining the country of origin for components of engines and transmissions in 583.8(c). While the minor items provision of 583.6 does not technically apply to the determinations made in

    583.8, we nonetheless conclude that suppliers of engines and transmissions may treat the cost of these minor items as value added in the country of assembly for purposes of 583.8 determinations. The National Highway Traffic Safety Administration adopted the minor items provision of 583.6 to avoid imposing on suppliers the unnecessary burden of having to obtain content information about minor items whose value was so small as to be unlikely to have any effect on overall content calculations. This rationale is equally applicable to 583.8 determinations.

    I hope this information is helpful. If you have any further questions, please call Edward Glancy of my staff at (202) 366-2992.

    Sincerely

    John Womack
    Acting Chief Counsel

    ref:583
    NCC-20:EGlancy:mar:3/21/01:62992:OCC 22222
    cc: NCC-01 Subj/Chron, Redbook (2), interp 583
    W:\nhtsaweb\cars\rules\interps\newhtml\22222.jeg.wpd



ID: nht78-3.6

Open

DATE: 09/07/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Motorcycle Trades Association, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your letter concerning the "edge treatment" requirements of Safety Standard No. 205, Glazing Materials, as they would apply to rigid or flexible plastics to be used for windshields on motorcycles. You asked for confirmation that one-piece plastics are required to meet the edge treatment requirements set forth in the standard for non-laminated glass.

The edge treatment requirements of Standard No. 205 are specified in paragraph S5.2, which incorporates by reference the SAE Recommended Practice J673a, "Automotive Glazing," August 1967. The SAE Practice specifies different requirements for "tempered" and "laminated" safety glass. The agency interprets the distinctions to apply equally to plastics. Therefore, one-piece plastic materials must meet the edge treatment requirements specified for "tempered" glazing, and laminated plastics must meet the requirements specified for "laminated" glazing.

Please contact this office if you have any further questions.

Sincerely,

ATTACH.

Motorcycle Trades Association, Inc.

June 13, 1978

Office of the Chief Counsel -- National Highway Traffic Safety Administration

Re: FMVSS No. 205 Paragraph S 5.2

In the above-mentioned section, edges of glazing materials (except in school buses) that are exposed must meet the requirements of SAE Recommended Practice J673a, August 1967.

The usual practice in the motorcycle industry is to use rigid or flexible plastics for windscreens and windshields for motorcycles. In most cases, these plastics meet the requirements of the ANSI Z26 standard in full; occasionally, these materials may use the (Illegible Word) from the chemical tests in Z26 when used in areas not requisite for driving visibility.

SAE J673a in virtually all of its wording speaks specifically of "Safety glass" and the edge treatment requirements differ for "tempered" and "laminated" materials. Please confirm for us that one-piece (that is, non-laminated) plastics materials are required to meet the edge treatment requirements set forth for non-laminated glass in the SAE standard.

Thank you for your assistance,

Bruce Henderson Vice-President, MTA

ID: 21886

Open


    Mr. Lawrence A. Beyer
    674 Lake Road
    Webster, NY 14580



    Dear Mr. Beyer:

    This is in reply to your letter of July 7, 2000, to Taylor Vinson of this Office.

    You asked: "Is it a violation of the Act or the Regulations for the owner of a vehicle to obtain US Title for the vehicle prior to the vehicle's importation?"

    We informed Philip Trupiano of Auto Enterprises on April 17, 2000, that it was permissible for a Registered Importer (RI) to obtain title to a vehicle in its own name before the conformance bond was released, but we did not address the question of titling a vehicle before its importation. A copy of that letter is enclosed.

    Under our statute, a RI must not license or register an imported vehicle for use on the public roads, or release custody of the vehicle to a person for license or registration for such use, unless the conditions of Section 30146(a) of Title 49 United States Code have been satisfied. Also, if a RI fails to conform a vehicle, it must be exported or abandoned to the Government according to the terms of the entry bond covering it (Section 30141(d)(1); Sec. 591.8; Sec. 592.6(j)).

    Under the statute, for permanent importations of vehicles, if a nonconforming vehicle is imported for personal use and not for resale under Section 30142, the statute does not prohibit its owner from obtaining a title before importation. Titling the vehicle in the name of its importer-owner does not affect either the obligation of the RI conforming the vehicle not to release it to the owner for registration until the conditions of Section 30146(a) have been satisfied, or the obligation of the owner to deliver the vehicle to Customs in the event that the vehicle has not been fully conformed.

    If a nonconforming vehicle is imported for resale, it must be imported by a RI. If a RI obtains a title in its own name before importation, this would not affect the other obligations of the RI, including but not limited to those to retain custody until the conditions of Section 30146(a) have been satisfied, and to deliver the vehicle to Customs upon demand if the RI fails to conform it. In light of the statute and given that these other obligations remain applicable, we do not believe that it is a violation of our laws and regulations for a RI to obtain title to a vehicle in its own name before the vehicle is imported.

    However, as we explained to Mr. Trupiano, a RI cannot obtain title in the name of its customer before the bond is released:

    One of the conditions of the bond is that the vehicle it covers be exported or abandoned to the United States in the event that an insufficient showing of conformity is made and the bond and the vehicle are not released. If the RI has transferred or reassigned title to the vehicle to "the customer on whose behalf the vehicle is imported" before the bond has been released, the RI cannot fulfill its duty to export or abandon the nonconforming vehicle because it would no longer own the vehicle. In that instance, NHTSA's sole remedy would be to foreclose on the bond. This is insufficient to fulfill the safety purpose of the statute and the bond which is to ensure that imported noncomplying vehicles be brought into compliance before being licensed for use, and used, on the public roads.

    This necessarily means that a RI cannot obtain title to a vehicle in the name of its customer before the RI imports the vehicle.

    Sincerely,

    Frank Seales, Jr.
    Chief Counsel

    Enclosure

    ref:591
    d.11/8/00



2000

ID: nht74-5.43

Open

DATE: 08/01/74

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Volkswagen of America, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your July 1, 1974, letter concerning Volkswagen's petition to exempt its pre-bent vacuum hose from some requirements of Standard No. 106-74, Brake hoses. You requested that we confirm that an in-line vacuum check valve is not regulated under the standard, and that the standard's use of "light duty" and "heavy duty" vacuum hose terminology corresponds to the use of those terms in the SAE Standard J1403a. We responded to the Volkswagen petition in a letter of July 2, 1974, to Mr. J. W. Kennebeck of Volkswagen.

You are correct in your conclusion that an in-line check valve like the valve in Volkswagen's pre-bent vacuum line is not a brake hose fitting subject to the requirements of Standard No. 106-74.

The National Highway Traffic Safety Administration tends to make the same distinction between light and heavy duty vacuum hose types as is made by the SAE Standard J1403a, which is based on the thickness of the hose wall. In addition to those sizes listed by the SAE we have added 9/32-inch hose.

YOURS TRULY,

VOLKSWAGEN OF AMERICA, INC.

July 1, 1974

Tad Herlihy, Esq. Office of Chief Counsel NHTSA

This will confirm our recent telephone conversation concerning FMVSS 106 applicable to brake hoses.

I understood you to say that Notice 11 of Docket 1-5 was not intended to serve as a response to our letter of April 26, 1974, which raised several questions concerning the applicability of S 9.2, 9.2.2, 9.2.3, 9.2.7 and 9.2.10 to certain pre-bent non-metallic vacuum hoses used by Volkswagen. You indicated that a separate response would be forthcoming in the near future.

You also confirmed that vacuum line check valves, regardless of where they are located in relation to the engine, whether in line, such as Volkswagen's, or directly connected to the engines, are exempt from Section 106.

In a separate telephone conversation, Mr. Ziwica raised the question as to whether the substance of the definition of "light and heavy duty vacuum brake(Illegible Word)" was identical to that used in SAE J 1403. I understand that it was the NHTSA's intent to incorporate the SAE definitional elements although somewhat different language was chosen. If my understanding is incorrect, please let me know as soon as possible.

Gerhard P. Riechel Attorney

cc: Mr. K.-H. Ziwica

ID: 1984-1.40

Open

TYPE: INTERPRETATION-NHTSA

DATE: 04/19/84

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Margaret Moore Oba -- Hino Motors (U.S.A.) Inc.

TITLE: FMVSS INTERPRETATION

TEXT:

MS. Margaret Moore Oba Hino Motors (U.S.A.) Inc. 200 Park Avenue, Suite 4116-12 New York, New York 10166

This responds to your March 12, 1984 letter regarding the applicability of Federal Motor Vehicle Safety Standards to motor vehicles imported into Guam.

Under sections 102(8), 102(9), and 108(a)(1)(A) of the National Traffic and Motor Vehicle Safety Act of 1966, 15 U.S.C. 1391(8), 1391(9), and 1397(a)(1)(A), motor vehicles introduced into commerce in Guam are subject to Federal Motor Vehicles Safety Standards. In general, the standards apply to the same extent to vehicles imported into Guam as to those imported into the continental U.S. However, as you note in your letter, FMVSS 103 (windshield defrosting and defogging systems) does not apply outside the continental U.S., as specified in section 3 of that standard. See 49 CFR 571.103. Other standards such as FMVSS 124, which do not limit their applicability to specific geographic areas, apply fully in Guam. Therefore, vehicles imported into Guam must have an accelerator control system which returns the throttle to idle over a temperature range of -40 degrees F. to +125 degrees F.

Original signed by Frank Berndt

March 12, 1984

Dear Mr. Berndt:

1) Re: Applicability of F.M.V.S.S. in Guam

We, Hino Motors, are a heavy duty diesel truck manufacturer, and are interested in importing Class 6 and 7 trucks to Guam and Saipan. We would appreciate if you would be so kind as to clarify the jurisdiction of the Federal Motor Vehicle Safety Standards (F.M.V.S.S.) in Guam. We are aware that the F.M.V.S.S. were made applicable to Saipan in 1978, and that dispensation from certain standards had been granted until October of 1981. We would like to know if the F.M.V.S.S. are applicable to Guam as well, and also, if there are any similar exceptions due to local conditions.

2) Re: F.M.V.S.S. 124

We would also like to receive clarification of the applicability of F.M.V.S.S. 124, regarding acceleration control systems. F.M.V.S.S. 103, Windshield Defrosting and Defogging Systems, is limited in its applicability to the fifty states of the United States. Is F.M.V.S.S. 124, which stipulates that the throttle be able to return to idle despite extreme temperatures ranging from -40oF to +125oF, applicable only to the continental U.S., or does it also apply to Hawaii and territories like Guam and Saipan?

We would greatly appreciate your prompt response to our inquiries. Thank you very much for your kind cooperation.

Original Signed by Margaret Moore Oba

cc: Mr. S. Ikoma, Tech. Div. Tokyo

ID: nht72-1.7

Open

DATE: 07/27/72

FROM: AUTHOR UNAVAILABLE; L. R. Schneider; NHTSA

TO: Ford Motor Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of June 20, 1972, to Mr. Toms concerning general reference material in support of the proposals contained in Docket No. 70-27. Hydraulic Brake Systems. You ask that the NHTSA place in the file "The supporting data upon which the test sequence is based as well as the data used to determine the performance values based on the sequence."

The proposed test sequence is based primarily upon the test sequence of standard No. 105, which is that of SAE Recommended Practice J937 incorporated by reference. Parking brake lightly loaded vehicle, inoperative brake power assist unit, and partial failure tests not included in J937, were placed in the sequence in the order that appeared, in the judgment of agency personnel, most likely to provide realistic and undistorted results. The sequence, of course, is subject to revision on the same basis in the forth-coming final rule. General reference material in the Docket includes data from braking tests of eighteen 1970 automobiles, NBS Technical Note 557, "The Brake Pedal Forces Capability of Adult Females," and SAE 720032, "Evaluation of the Use of Automotive Braking Systems During a 7300 Mile Cross-Country Trip."

ID: nht95-2.37

Open

TYPE: INTERPRETATION-NHTSA

DATE: April 14, 1995

FROM: Philip R. Recht -- Chief Counsel, NHTSA

TO: David A. White -- Manager of Reliability, Grumman Olson

TITLE: NONE

ATTACHMT: ATTACHED TO 3/14/95 LETTER FROM DAVID A. WHITE TO NHTSA ADMINISTRATOR

TEXT: Dear Mr. White:

This responds to your letter of March 14, 1995, requesting the National Highway Traffic Safety Administration (NHTSA) to approve an alternate location for placement of the certification label on certain vehicles manufactured by Grumman Olson. Your lette r describes those vehicles as van bodies mounted on either cutaway chassis or chassis cabs that are sold as part of Grumman Olson's Freight Star line. Your letter further states that as chassis manufacturers have made changes to the doors and interiors of their vehicles, Grumman Olson has found it "increasingly difficult, if not impossible" to locate its certification label, which measures three and one half by six inches, in any of the locations specified in NHTSA certification regulations at 49 CFR 5 67.4.

Paragraph (c) of that section prescribes specific locations for the installation of vehicle certification labels, and provides that if none of those locations are practicable, the manufacturer may suggest an alternate location for NHTSA's approval. The location that you have recommended is on the forward half of the left side of the cargo box, which is the same location as the one specified in 49 CFR 567.4(d) for the placement of certification labels on trailers. In a photograph that you subsequently faxed to us, the proposed location was more precisely identified as the left front corner of the cargo box, immediately behind the cab.

In specifying locations for the placement of vehicle certification labels, NHTSA's objective is to ensure that those labels may be easily read. The location that you have proposed for vehicles in Grumman Olson's Freight Star line would meet this objecti ve. NHTSA therefore approves your request.

To ensure that vehicles manufactured for sale in the United States may be distinguished from those manufactured for sale in Canada, NHTSA strongly suggests that the letters "U.S." or "U.S.A." be inserted before the word "Federal" in the safety standard c ompliance statement that must be included in the certification label under 49 CFR 567.4(g)(5).

If you have any further questions regarding vehicle certification requirements, feel free to contact Coleman Sachs of my staff at the above address, or by telephone at (202) 366-5238.

ID: nht73-1.36

Open

DATE: 07/26/73

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Signal-Stat Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of July 10, 1973, to Mr. Schneider asking which SAE Standard incorporated into Standard No. 108 applies to turn signal operating units, SAE J589 or J589a.

The correct standard is SAE J589. You noted that the tables in the standard refer to J589, while paragraph S5.1 states that subreferenced standards shall be those published in the 1970 edition of the SAE Handbook. The key word in S5.1 is "subreferenced", i.e., referred to only in an SAE standard itself referenced in the Federal standard. J589 is directly referenced, not subreferenced and the number identified is correct. An example of a subreferenced standard would be J575, which is mentioned in J589.

Your truly,

July 10, 1973

Office of Chief Counsel -- National Highway Traffic Safety Administration

Attention: L. Schneider

Gentlemen:

We will appreciate in obtaining your interpretation relative to the testing regulations of the "Turn Signal" operating units.

I. FMVSS#108, paragraph S.5.1 states:

"S5. 1 SAE Standards and Recommended Practices subreferenced by the SAE Standards and Recommended Practices included in Tables I and III and paragraphs S4.1.4 and S4.5.1 are those published in the 1970 edition of the SAE Handbook".

The 1970 SAE edition of SAE Standards contains SAE J-589a for Turn Signal operating units.

II. On the other hand, Tables I & III of FMVSS #108 specifies SAE J-589 for Turn Signal operating units. Is it a conflict between paragraph S5.1 and the Tables I and III of FMVSS #108?

Please inform which of the two mentioned SAE Standards is applicable for 1973, J-589a or J-589.

Thank you for your cooperation.

Very truly yours, SIGNAL-STAT CORPORATION --

Rene Politis, Director, Product Reliability and ASSURANCE DEPT.

ID: nht79-2.44

Open

DATE: 03/27/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: L. B. Leiby

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of February 7, 1979, to the Department asking about the legality of wiring the rear hazard warning signals so that they automatically flash when the gear shift lever is placed in reverse.

We are able to give you guidance about applicable Federal law only. The Federal requirements for new motor vehicles are set forth in Federal Motor Vehicle Safety Standard No. 108 (49 Code of Federal Regulations 571.108). As you probably know, the hazard warning system and the turn signal system typically use the same lights. There is no provision in the standard which prohibits a manufacturer from wiring the rear hazard signals/turn lights so that they flash when the vehicle gear shift is in reverse. Please note, however, that the standard (S4.6(b)) requires the separate rear tail lamps to be steady burning. Thus, those lamps may not be wired so that they flash.

As for modification of used vehicles, contact the State in which the modified vehicle would be licensed and operated to determine if it has any applicable vehicle-in-use laws.

We appreciate your interest in motor vehicle safety.

SINCERELY,

7 February 1979

Dear Sir,

I am working on a concept which if legal and feasible, will, I believe, reduce accidents in parking areas.

The concept concerns the utilization of blinker lights normally used for highway emergency purposes to be wired to the backup lights circuit so that when the gear shift lever is placed in reverse, the red tail lights will automatically blink thus providing extra warning to oncoming drivers in parking areas.

Can you provide information as to the legality of the above concept, and please include any related factors.

Thank you.

Lawrence B. Leiby

Request an Interpretation

You may email your request to Interpretations.NHTSA@dot.gov or send your request in hard copy to:

The Chief Counsel
National Highway Traffic Safety Administration, W41-326
U.S. Department of Transportation
1200 New Jersey Avenue SE
Washington, DC 20590

If you want to talk to someone at NHTSA about what a request for interpretation should include, call the Office of the Chief Counsel at 202-366-2992.

Please note that NHTSA’s response will be made available in this online database, and that the incoming interpretation request may also be made publicly available.

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