Interpretation ID: nht89-2.31

TYPE: INTERPRETATION-NHTSA

DATE: 07/10/89

FROM: STEPHEN P. WOOD -- NHTSA ACTING CHIEF COUNSEL

TO: SADATO KADOYA -- MANAGER, SAFETY ENGINEERING MAZDA (NORTH AMERICA), INC. RESEARCH & DEVELOPMENT CENTER

TITLE: NONE

TEXT: Dear Mr. Kadoya:

This is to provide you with a clarification of our letter to you dated November 3, 1988, based upon your telephone conversation with Taylor Vinson of this Office.

Our letter advised you that Standard No. 108 did not preclude the use of replaceable bulb headlamps with adjustable reflectors. In reply, you have cited two provisions of the standard which appear in conflict with this interpretation. With respect to a headlamp equipped with one or two HB1 light sources, S4.1.1.36(e)(1) states that "There shall be no mechanism that allows adjustment of an individual [HB1] or adjustment of reflector aim with two [HB1s]." To similar effect with respect to HB3 and HB4 li ght sources is S4.1.1.36(f)(1). Standard No. 108 has been amended effective June 8, 1989, and the corresponding requirements are now S7.5(d)(1) and (e)(1). Each has been revised to state "There shall be no mechanism that allows adjustment of an individ ual light source, or, if there are two light sources, independent adjustment of each reflector."

We believe that the revised wording of the new sections clearly allow the adjustment of single reflectors in single light source replaceable bulb headlamps, and dual reflectors in dual-light source replaceable bulb headlamps, provided that the reflectors are not capable of independent adjustment. Further, new S7.7.2.2 specifically addresses how moveable reflectors must operate.

The intent of these sections is to prohibit headlamp designs in which the bulb alone is adjusted to aim the headlamp since this is contrary to

mechanical aim requirements, or, where there is more than one reflector in a headlamp, designs in which each reflector may be adjusted independently, since this is also contrary to achieving precise mechanical aim.

Thank you for bringing this matter to our attention.

Sincerely,