Interpretation ID: nht70-2.45

DATE: 12/30/70

FROM: AUTHOR UNAVAILABLE; R. H. Compton; NHTSA

TO: The Grote Manufacturing Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of December 5, 1970, to Mr. Julian E. Ieysath of this office concerning mounting of clearance lamps and testing combination lamps.

The wording for the mounting requirements of clearance lamps was amended in Standard No. 103 (35 F.R. 16040) to provide clarification; there was no intent to change the actual requirements. S4.3.1.7 permits clearance lamps in Standard No. 103 (35 F.R. 16840) to provide clarification; there was no intent to change the actual requirements. S4.3.1.7 permits clearance lamps to be mounted on the cab of a truck tractor, which in many cases may not indicate the overall width of the vehicle.

Section L of SAE J575, as modified by S4.2.1 of the amended standard, states, "The device shall be operating in the test in the same manner as it will be operated in service." Combination lamps have therefore been tested for less warpage with the steady burning tail or parking lamp operating continously and with the turn signal flashing. Now that the lens warpage test will also apply to the stop and backup lamps, this Bureau will test a combination lamp under the most severe possible operating condition. Since it is possible to have the tail, stop and backup lamps on simultaneously, these functions will be operating during the test for the stop and backup lamp lenses. A second test with the tail, turn signal and backup lamps operating will also be conducted.

Petitions for reconsideration have been received in Docket 69-18 requesting that the 10 minute cycling test be changed to 5 minutes on and 5 minutes off or that the effective date for the stop and backup lamp lens warpage requirement be extended beyond the July 1, 1971, effective date. Our decisions on these petitions will be published in the Federal Register in the near future.