Interpretation ID: nht72-2.24

DATE: 05/09/72

FROM: AUTHOR UNAVAILABLE; D. W. Toms; NHTSA

TO: Department of California Highway Patrol

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of April 18, 1972, requesting an interpretation of the requirements of Federal Motor Vehicle Safety Standard No. 108 which relates to the use of mechanical aimers on headlamps.

Standard No. 108 references, in Tables I and III, SAE Standard J580a. As stated in your letter, SAE J580a specifies in part that "Headlamps shall be designed so that they may be checked by mechanical aimers without the removal of any ornamental trim rings or other parts." The language in this requirement, and that contained in other referenced and subreferenced SAE standards, does not specifically identify the design or complete dimensional details of "mechanical aimers." Therefore, the use of any mechanical aimer, including those fitted with special adapters for specific vehicles, would be permitted under the above stated requirement.

Specifically, you asked, "If a vehicle is so designed that the headlamps cannot be checked with mechanical aimers of the type now commonly available without the removal of ornamental trim rings or other parts, does it meet the requirements of Federal Standard 108?" A "commonly available" aimer is defined as one that is manufactured and offered for sale, including an aimer with adapters for special applications. A vehicle which is so designed that the headlamps cannot be checked with mechanical aimers as thus defined, without the removal of ornamental trim rings or other parts, would not meet the requirements of Standard No. 108.