Legal & Homologation Section
Stanley Electric Co., Ltd.
2-9 13, Nakaameguro, Meguro-ku
Tokyo 153, Japan
Re: Accessory Lamp with LEDs
Dear Mr. Matsui:
This responds to your letter of September 18, 1995, describing a combination tail, stop, and rear turn signal lamp which incorporates incandescent bulbs to perform assigned functions, and which contains light- emitting diodes (LEDs) in a compartment along the outboard side.
With respect to red LEDs adjacent to the tail and stop lamp, you state that the lamp is designed to conform to Standard No. 108 using the incandescent bulbs only, and that you regard the LEDs as an "accessory" acceptable to NHTSA (Your Question 1).
We agree. Because the LEDs are not necessary to conformance with Standard No. 108, they are considered supplemental lighting equipment. Such equipment is permitted by paragraph S5.1.3 of Standard No. 108 if it does not impair the effectiveness of lighting equipment required by Standard No. 108. You state that when the taillamp and LEDs are lit simultaneously, the total intensity does not exceed the maximum intensity specified for a one-section taillamp. It would therefore appear that the presence of the LEDs does not impair the effectiveness of the taillamp (or the stop lamp, which will have a higher intensity).
The red LEDs will provide a red color through the amber lens that covers the turn signal lamp, and will remain on when the turn signal is activated (Your Question 2). This design also appears permissible. We have never considered contiguous rear steady-burning red and flashing amber lamps to be prohibited by Standard No. 108 (the basic design of your lamp), and we do not believe that the supplemental red LEDs will impair the effectiveness of the amber turn signal lamp.
If you have any further questions, you may refer them to Taylor Vinson of this Office (phone: 202-366-5263).
Samuel J. Dubbin Chief Counsel