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Windows - Rear Defogger Automatic Time Out Feature

File In Section: 8 - Chassis/Body Electrical

Bulletin No.: 73-82-08

Date: June, 1997

INFORMATION

Subject:
Rear Defogger Operation
(Time On/Time Out)

Model:
1997 Buick Riviera

Vehicles built prior to March 1, 1997, have a rear window defogger solid state timer that "times out" after 10 minutes regardless of vehicle speed. Each time the rear defogger switch is pressed thereafter in the same key cycle, the timer resets to operate for 5 minutes.

Vehicles built after March 1, 1997, have a rear window defogger timer that has been reprogrammed. The rear window defogger in these vehicles will operate for approximately 10 minutes. However, if the vehicle is traveling over 48 km/h (30 mph), the timer function is disabled and the defogger operates continuously. When the vehicle speed is less than 48 km/h (30 mph), the rear window defogger will "time out" at approximately 10 minutes. Each time the rear defogger switch is pressed thereafter in the same key cycle, the timer resets to operate for 5 minutes if vehicle speed is less than 48 km/h (30 mph).