Interpretation ID: 20949.ztv

Mr. William T. Smith
110 Spear Street
Metuchen, NJ 08840-2126

Dear Mr. Smith:

This is in reply to your letter of November 3, 1999, to the agency on daytime running lamps (DRLs). It was your impression that all 2000 model year passenger cars were required to have DRLs, and you ask if you may have them installed on your new Mercury without voiding the vehicle's warranty.

Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices and Associated Equipment, requires motor vehicles to be manufactured in compliance with its specifications. Under Standard No. 108, DRLs are not a required lighting system, but the standard permits manufacturers to install a DRL system if they wish. If the manufacturer exercises this option, the DRL system must comply with the requirements specified in Standard No. 108.

Ford Motor Company, the manufacturer of your new car, chose not to equip it with a DRL system. This agency does not regulate or review vehicle warranties. It is possible that certain aspects of your vehicle warranty could be voided by altering the vehicle wiring were you to have a DRL system installed by a person not authorized by Ford. We recommend that you contact Ford's Zone Office for its opinion.

Your local mechanic is allowed to install a DRL system on your car under Federal law, provided that the mechanic does not make inoperative any element of design or device installed in accordance with one of the Federal motor vehicle safety standards. We interpret this to mean that an aftermarket DRL system is permissible as long as it does not interfere with the performance of other lighting equipment and conforms to the specifications of Standard No. 108 for an original equipment DRL system. Our greatest concern is that an aftermarket DRL system not exceed the maximum luminous intensity limits. For example, a lower beam headlamp may be wired to operate as a DRL at full voltage, but an upper beam headlamp may not.

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

Sincerely,
Frank Seales, Jr.
Chief Counsel
ref:108
d.4/27/00