Interpretation ID: aiam2942
Administrator
Vehicle Regulations
Volkswagen of America
27621 Parkview
Boulevard
Warren
MI 48092;
Dear Mr. Haenchen: This is in reply to your letter of January 3, 1979, asking fo confirmation of your interpretation of Federal Motor Vehicle Safety Standard No. 108 as it applies to a braking system that Volkswagen proposes to use on its 1980 Dasher model.; Specifically, the Dasher will employ a single 'pressure switch on eac vehicle, meaning that the stop lamp will be activated by only one of the [two, split] service brake systems.' You asked whether this is consistent with S4.5.4 of Standard No. 108 which requires that 'the stop lamps on each vehicle shall be activated upon application of the service brakes.' You argued that it meets the standard because:; >>>'Neither FMVSS 571.105-75 nor 575.108 (sic) clearly specify th conditions under which the stop lights have to operate. Specifically, the regulations do not specify that the stop lamps must illuminate upon application of the service brake control if one of the circuits of a dual circuit hydraulic braking system failed.'<<<; We do not concur with your interpretation. S4.5.4 quite clearl specifies the conditions under which the stop lamps must operate--'upon application of the service brakes,' and it is immaterial which circuit of a dual circuit hydraulic braking system is braking the vehicle. Therefore, your proposed system would constitute an apparent noncompliance with Standard No. 108.; Sincerely, Joseph J. Levin, Jr., Chief Counsel