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Interpretation ID: nht95-3.40

TYPE: INTERPRETATION-NHTSA

DATE: July 10, 1995

FROM: Ricardo Martinez -- M.D., NHTSA

TO: Shih-Chiang Chen -- President, Top World Traffic Equipments Co., Ltd.

TITLE: NONE

ATTACHMT: ATTACHED TO 6/15/95 LETTER FROM SHIN-CHIANG CHEN TO DOT MINISTER

TEXT: Dear Sir:

This is in reply to your letter of June 15, 1995, to the Department of Transportation regarding your invention, the "brake condition warning sensor." You ask whether such an invention is permissible in this country.

The sensor causes flashing in "the third brake light" keyed to the rate of deceleration.

Under the Federal regulations in the United States, motor vehicles must be manufactured so that the third brake light (or "center highmounted stop lamp" as we call it) and all other stop lamps are steady-burning when they are in use.

After the vehicle is sold, Federal law prohibits any manufacturer, dealer, distributor, or motor vehicle repair business from installing the sensor to modify the performance of the third brake light and cause it to flash.

However, Federal law does not prohibit the owner of the car from installing the sensor. In this circumstance, the law of the State in which the vehicle is operated must be consulted to determine whether a flashing third brake light is permissible. We a re not able to answer questions about State laws. If you wish an opinion on State laws governing flashing third brake lights, you should write the American Association of Motor Vehicle Administrators, 4600 Wilson Boulevard, Arlington, Va. 22203.

If I can be of further assistance, please contact me or Mr. John Womack Acting Chief Counsel (202) 366-9511.