Interpretation ID: aiam4392
Adaptive Driving Service
2818 Ronco Drive
San Jose
CA 95132;
Dear Ms. Tate: This is in reply to your letter of August 13, 1987, with reference t the following problem: an owner of a 1987 Toyota Corolla has multiple sclerosis, and instead of walking must use a powered scooter. The scooter is transported by a lift platform mounted on a trailer hitch in the rear of the car. However, this lift unit 'obstructs direct view of the factory installed high rear brake light.' You propose to install another stop lamp on the post of the lift 'so that it will be in direct view of the drivers behind....,' leaving untouched the original center highmounted stop lamp. You have informed us that California will not sanction the additional lamp unless this agency authorizes it.; Vehicles in use are subject to the prohibition in the National Traffi and Motor Vehicle Safety Act that equipment installed in accordance with a safety standard may not be rendered inoperative, in whole or in part, by a person other than the vehicle owner. Installation of any equipment that obstructs the light output of a highmounted stop lamp would render it partially inoperative in our opinion. Because photometric compliance of the lamp is determined from a distance of not less than 10 feet, and because the distance between the Toyota rear lamp and lift unit would appear to be less than that distance, it is probable that one or more of the requisite photometric test points might be obscured by the device.; However, it appears that the prohibition against rendering inoperativ may not be violated by the modification you propose. Federal Motor Vehicle Safety Standard No. 108, *Lamps, Reflective Devices, and Associated Equipment* allows an exception for modifications made during the manufacturing process or before sale. Under Paragraph S4.3.1.1, if motor vehicle equipment prevents a lamp from compliance with photometric requirements, an auxiliary lamp meeting the photometric requirements shall be provided. Where a standard provides alternative methods of compliance, alteration of a vehicle or item of equipment so that it meets a different alternative from the one which it originally met does not constitute rendering inoperative within the meaning of the prohibition. We believe that your situation is sufficiently similar so that your addition of an auxiliary lamp meeting the photometric requirements would not violate the prohibition. In this instance the fact that the new lamp would not be located directly on the rear vertical centerline of the vehicle, but slightly to the left of it, would not be of great concern to us. In conclusion, we have no objection to the proposed installation of the lamp.; Sincerely, Erika Z. Jones, Chief Counsel