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    Mr. Stuart McKenzie
    McKenzie Auto Consulting Limited.
    254 Dereham Road
    New Costessey
    NR5 0SN, England

    Dear Mr. McKenzie:

    This responds to your request for our legal opinion concerning Federal Motor Vehicle Safety Standard (FMVSS) No. 103, Windshield Defrosting and Defogging Systems. You have a client that is manufacturing an electric vehicle for sale in the United States. This vehicle "will be fitted with an electrically heated front windshield that will solely provide the defrosting and defogging functions required by FMVSS 103". You ask about test procedures under S4.3(a) and (b) of the standard, as they apply to electric vehicles.

    By way of background information, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue FMVSSs, which apply to new motor vehicles and new items of motor vehicle equipment manufactured for sale, sold, offered for sale, introduced or delivered for introduction in interstate commerce or imported into, the United States of America. (See Title 49 of the United States Code Section 30112.) NHTSA does not provide approvals of motor vehicles or motor vehicle equipment. Instead, manufacturers are required to certify that their vehicles and equipment meet applicable standards.

    In a final rule of March 9, 1994 (59 FR 11004, copy enclosed), we amended FMVSS No. 103 to make the standard more appropriate for electric powered motor vehicles. As amended, S4.3(a)(1) and (b)(1) provide that for a passenger car equipped with a heating system other than a heat exchanger type that uses the engines coolant as a means to supply the heat to the heat exchanger, the warm-up procedure is that specified by the manufacturer for cold weather starting, except that connection to a power or heat source external to the vehicle is not permitted.

    You suggested the following procedure: switch the ignition switch to "run" and set the defrosting and defogging control to maximum. If this procedure is "the warm up procedure that is specified by the manufacturer for cold weather starting", it would be the one used pursuant to S4.3(a) and (b).

    I hope this information is helpful. If you have any further questions, please feel free to contact Dorothy Nakama of my staff at this address or by telephone at (202) 366-2992.


    Stephen P. Wood
    Acting Chief Counsel