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

Step

Action

Normal Result(s)

Abnormal Result(s)*

1

Turn the ignition switch to the RUN position.
    • The rear defogger on indicator is off.
    • The rear defogger is off.

2
  1. Press and release the rear defogger switch 1 time.
  2. Wait approximately 11 minutes.
    • The rear defogger on indicator comes on.
    • The rear defogger turns on.
    • The rear defogger on indicator and the rear defogger turns off after 10 minutes.

3
  1. Press and release the rear defogger switch 1 time.
  2. Wait 6 minutes.
    • The rear defogger on indicator comes on.
    • The rear defogger turns on.
    • The rear defogger on indicator and the rear defogger turn off after 5 minutes.

4
  1. Press and release the rear defogger switch 1 time.
  2. Press and release the rear defogger switch a second time. This must be done before time-out occurs.
    • The rear defogger on indicator comes on.
    • The rear defogger turns on.
    • Pressing the switch for the second time causes the rear defogger on indicator and the rear defogger to turn off immediately.

* Refer to the appropriate symptom diagnostic table for the applicable abnormal result.