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Search Interpretations

Interpretation ID: nht73-3.9

DATE: 01/11/73

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Pilot, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: In your letter of December 15, 1972, to the Department, you ask "Do the regulations require that the brake lite be activated prior to the onset on any brake pressure due to pedal travel can some brake pressure be on before the brake lite lights?"

Paragraph S4.5.4 of Motor Vehicle Safety Standard No. 108 Lamps Reflective Devices and Associated Equipment requires that "the stop lamps shall be activated upon application of the service brake." The standard does not state a specific time or brake line pressure at which activation shall occur so that some brake pressure is permitted at the activation point.