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Interpretation ID: 23912.ztv



    Mr. Denis Igoe
    Automotive Lighting
    47000 Liberty Drive
    Wixom, MI 48393


    Dear Mr. Igoe:

    This is in reply to your fax of January 16, 2002, to Taylor Vinson of this Office, asking for an interpretation of Federal Motor Vehicle Safety Standard No. 108 as it pertains to visually-optically aimable (VOA) headlamps.

    You identified yourself as working in the automotive industry" for a "forward lighting manufacturer." With respect to a headlamp currently in production, you wrote that "a proposal for cost savings is to eliminate the horizontal VHAD and the ability to adjust in the horizontal." As you see it, "the issue becomes: through vehicle service it is possible a new headlamp w/o horizontal adjustment (& VHAD) could be paired with an old headlamp with horizontal adjustment (& VHAD) on the very same vehicle." You have asked, "aiming instructions notwithstanding, is this situation compliant or not, with existing NHTSA regs?"

    Section S7.8.5.3(b) of Standard No. 108, applicable to VOA headlamps, prohibits horizontal adjustment of horizontal aim of the lower beam of a headlamp unless the headlamp is equipped with a horizontal VHAD. Thus a horizontal aim adjustment feature is not a requirement for VOA headlamps but an option of the headlamp manufacturer. The situation you posit is one in which a vehicle in service could have one lower beam that was horizontally adjustable and the other lower beam would not be horizontally adjustable.

    This headlamp mixture would not be permissible as original equipment on new motor vehicles. Some years ago we were asked by Robert Bosch GmbH whether it would be permissible to install on one side of a vehicle a headlamp with VHAD (onboard aiming) for vertical aim and on the opposite side a VOA headlamp in the case where a vehicle manufacturer wanted to change from VHAD-headlamps to visually aimable headlamps during the production of a certain vehicle type. On March 10, 1998, we replied to Bosch (see the enclosed letter to Tilman Spingler) that "all headlamps within a headlighting system must comply with the same set of requirements, including its aiming features."

    We have addressed the issue of compatibility of replacement headlamps in both the preamble to the final rule adopting VOA headlamps and in an interpretation letter to Stanley Electric Co. dated June 22, 1998 (copy enclosed). In the preamble, we observed that "any current headlamp design that is modified to include visual/optical aimability must still provide mechanical aimability if that headlamp is intended to be a replacement in vehicles in which the lamp was used before its redesign" (62 FR 10710 at 10714, March 10, 1997). Citing that language, Stanley informed us that it would modify headlamp aiming features on an existing model headlamp for a new model year headlamp but would continue producing the old design for replacement purposes. The two headlamp designs would have different parts numbers and lens identifiers. Stanley asked for confirmation that the new system need not continue to provide mechanical aimability. We replied to Tadashi Suzuki of Stanley on June 22, 1998, stating that we did not consider the new design to be a "replacement" requiring retention of the mechanically aimable feature because the two headlamps would have different part numbers and lens identifiers. We also advised that Stanley's intent would be "even clearer if the cartons in which each type of replacement headlamp is shipped are marked to identify the specific model year(s) for which replacement is intended."

    In your fact situation, we assume that mechanical aimability is not an issue, and that both headlamps are VOA in type. Nevertheless, as we also advised Stanley, "[I]t is not advisable for headlamp on the same vehicle to have to be aimed by two different means." Accordingly we would encourage you to take steps to distinguish the new and old headlamp designs by the means that we suggested to Stanley (different part numbers, lens identifiers, carton marking), to minimize the possibility that a replacement headlamp might be installed that is not identical to the original headlamp, thereby creating a headlighting system that would not comply with the original equipment requirements of Standard No. 108.

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

    Sincerely,

    Jacqueline Glassman
    Chief Counsel

    Enclosures
    ref:108
    d.4/5/02