Interpretation ID: nht89-1.48
TYPE: INTERPRETATION-NHTSA
DATE: 03/22/89
FROM: SAMUEL KIMMELMAN -- PRODUCT ENGINEERING MANAGER PARKER HANNIFIN CORP
TO: TAYLOR VINSON -- LEGAL COUNCIL FMVSS-108 NHTSA U.S. DEPARTMENT OF TRANSPORTATION
TITLE: NONE
ATTACHMT: ATTACHED TO LETTER DATED 11/01/89 FROM STEPHEN P. WOOD -- NHTSA TO SAMUAL KIMMELMAN -- PARKER HANNAFIN; REDBOOK A34; STANDARD 108
TEXT: Dear Mr. Vinson:
It is our understanding that FMVSS-108 allows vehicles with combined function rear stop and turn signal/hazard lamps to operate in either of two modes when both the hazard switch and brake switch have been actuated.
1. The hazard switch is the major control for operation of the combined rear stop and turn signal/hazard lamps.
a. Actuating the hazard switch some period of time after actuation of the brake switch will cause the rear lamps to change from steady on, stop signal, to flashing, hazard signal.
b. Actuating the brake switch some period of time after actuation of the hazard switch will not change the flashing lamps, hazard signal, to steady on, stop signal.
2. The brake switch is the major control for operation of the combined rear stop and turn signal/hazard lamps.
a. Actuating the brake switch some period of time after actuation of the hazard switch will cause the rear lamps to change from flashing, hazard signal, to steady on, stop signal.
The front flashing hazard lamps will also become steady on.
b. Actuating the hazard switch some period of time after actuation of the brake switch will not change the rear steady on lamps, stop signal, to flashing, hazard, while the front hazard lamps go from off to steady on.
Is our interpretation of what is allowed by FMVSS-108 regarding the operation of vehicles with combined function rear stop and turn signal/hazard lamps upon actuation of both the hazard and brake switces correct?
If our interpretation of FMVSS-108 is correct, is NHTSA presently considering a NPRM to specify a specific signal from the combined function rear stop and turn signal/hazard lamps when both the hazard and brake switches are actuated?
Sincerely,