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Interpretation ID: nht68-2.6

DATE: 05/14/68

FROM: AUTHOR UNAVAILABLE; David A. Fay; NHTSA

TO: White Motor Corporation

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of April 16, 1968, to Mr. Lowell K. Bridwell, Administrator, Federal Highway Administration, requesting a clarification of the electrical circuity arrangements that may be used to meet the requirements of paragraph S3.4.3 of Motor Vehicle Safety Standard No. 108.

Truck-tractors wired in accordance with your customers' orders stating, "the brown trailer circuit shall be connected to the headlamp switch and the black trailer circuit shall be energized through a seperate switch," will meet the requirements of paragraph 53.4.3, provided the trailer circuits conform to SAE Standard J560a. With this circuitry, your responsibility as a truck-tractor manufacturer would be fulfilled, regardless of the number of trailers that are towed by the truck-tractor.

Thank you for writing.