GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 1999 🢒 Eighty Eight 🢒 Body and Accessories 🢒 Stationary Windows 🢒 Defogger System Check

Step

Action

Normal Result(s)

Abnormal Result(s)

1
  1. Ignition ON.
  2. Turn the rear defogger switch ON.

The indicator light on the rear defogger switch will illuminate and the rear defogger will be operational.

The indicator light will not illuminate and the defogger will not operate. Refer to Rear Window Defogger Inoperative .

2

Ignition in RUN position.
    • The indicator light on the rear defogger switch will illuminate and the rear defogger will operate.
    • The indicator light will turn off and the rear defogger will not operate after a 5-10 minute cycled time period.

The indicator light is on, the rear defogger is operating and continues after approximately a 10 minute time period. Refer to Defoggers and Heated Mirrors Always On .