Interpretation ID: 17632.ztv

Mr. L. W. Camp
Director
Automotive Safety Office
Ford Motor Company
300 Town Center Drive
Dearborn, MI 48126

Dear Mr. Camp:

This is in reply to your letter of March 23, 1998, with respect to an interpretation of "permanent" fixation of vehicle headlamp aiming device (VHAD) calibration.

Paragraph S7.8.5.2(c) of Federal Motor Vehicle Safety Standard No. 108 requires that "Each headlamp equipped with a VHAD that is manufactured for use on motor vehicles manufactured on or after September 1, 1998, shall be manufactured with its calibration permanently fixed by its manufacturer." You reference our letter to Ichikoh Industries dated June 11, 1997, in which we said that if the calibration is capable of adjustment by any means it is not "permanent." You believe that this interpretation is not in accord with the intent of the rulemaking "and if read literally creates an impracticable and unreasonable standard." You have asked for an additional clarification of the term "permanent."

In your opinion, "the intent of the term 'permanent' was to help prevent adjustment of the VHAD calibration by either service mechanics or the operator, once set by the manufacturer. This would facilitate the proper aim of headlamps equipped with VHAD devices in the field. The [Regulatory Negotiation] Committee never intended that headlamp manufacturers prevent a determined individual from deliberately altering the calibration, as this is neither reasonable nor practicable."

You believe that S7.8.5.2(c) would be satisfied if a VHAD is tamper resistant or tamper indicant. With respect to tamper resistance, you write that a system could be designed so that the calibration mechanism would not permit misadjustment by a customer using ordinary tools or by a dealer using special tools provided only by the vehicle manufacturer. Ford also believes that if a vehicle is designed so that the vehicle structure prevents access to the VHAD calibration mechanism, the calibration should be considered "permanently fixed." Ford also believes that the term "tamper indicant" can be synonymous with "permanent."

Analogizing to emission control calibration systems incorporating a cap which must be destroyed in order to defeat the manufacturer's emission control calibration setting, you believe that a similar cap design could prevent "anyone aiming a headlamp from inadvertently making an adjustment of the VHAD calibration."

I would like to explain our interpretation to Ichikoh Industries in light of the concerns you raise. We disagree that the intent of the requirement for "permanent" calibration is to help prevent adjustment of the VHAD calibration by just service mechanics or vehicle owners. The intent is to prevent adjustment by vehicle distributors and dealers as well. We also acknowledge that headlamp manufacturers cannot design a system that will absolutely prevent intentional tampering. We believe that the test for determining whether calibration is permanent is whether it is tamper-resistant both with respect to owners, service mechanics, vehicle distributors, and vehicle dealers.

The specific question asked by Ichikoh Industries was "(d)oes calibration method that vehicle owner or driver cannot calibrate using ordinary tools conform to [the requirement for permanent calibration]?" As we noted in our reply, this question implied that the calibration could be adjusted by tools that are not "ordinary tools." We stated that if the calibration is capable of adjustment by any means, it is not permanent, and that if the calibration cannot be adjusted, by ordinary tools or otherwise, then it is permanent.

I note that the question we were answering was asked in the context of calibration being performed by a vehicle owner or driver. The point we were trying to make in answering the question was that just because a vehicle owner or driver would need to obtain and use special tools to calibrate the VHAD device would not be sufficient to make the headlamp manufacturer's calibration permanent. However, this principle would not apply in a situation where special tools existed but the headlamp manufacturer reasonably believed that the tools would not available to the public, including service mechanics and vehicle distributors and dealers. This is because, in such a situation, neither a vehicle owner nor a mechanic could obtain or use such tools to calibrate the VHAD device.

We cannot provide an interpretation as to whether a particular design would be tamper-resistant outside the context of specific information about the design. We would be cautious, however, with respect to the approach of making systems "tamper indicant" as opposed to tamper-resistant. In our view, the mere fact that it would become readily apparent that a system has been calibrated would not, by itself, necessarily discourage such calibration. Thus, unless such systems could also be viewed as tamper-resistant, we would not consider them to be "permanent" in the context of the requirement at issue.

We do not agree with Ford's view that the calibration is "permanently fixed" if a vehicle is designed to prevent access to the VHAD calibration feature. Although Ichikoh asked a similar question regarding vehicle structures and aiming devices, its question was in the context of horizontal aiming systems and not calibration. We advised Ichikoh that if the horizontal aiming mechanism was not accessible for aiming the headlamp, it would be regarded as absent for purposes of meeting Standard No. 108. Ford's question is whether the VHAD calibration can be regarded as "permanently fixed" if the VHAD is inaccessible when the headlamp is installed on a vehicle. The answer is no; Standard No. 108 clearly states that the VHAD calibration is to be fixed by the headlamp manufacturer at the time the headlamp is manufactured. This means that its accessibility when the vehicle manufacturer installs the headlamp is irrelevant to the issue of whether its calibration is "permanently fixed."

If you have any questions, you may call Taylor Vinson of this Office (202-366-5263).

Sincerely,
Frank Seales, Jr.
Chief Counsel
ref:108
d.6/18/98