GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1998 🢒 Riviera 🢒 Body and Accessories 🢒 Stationary Windows 🢒 Defogger System Check

Step

Action

Normal Result(s)

Abnormal Result(s)*

1

Start the engine.
    • The defogger ON indicator is off.
    • The defogger is off.
    • Go to Rear Window Defogger Always On

2
  1. Press and release the defogger switch once.
  2. Wait approximately 11 minutes.
    • The defogger indicator illuminates.
    • The defoggers turn on.
    • The defogger indicator and the defogger turn off after approximately 10 minutes.
    • Go to Rear Window Defogger Always On

3
  1. Press and release the defogger switch once.
  2. Wait 6 minutes.
    • The defogger indicator illuminates.
    • The defoggers turn on.
    • The defogger indicator and the defogger turn off after 5 minutes.

Rear Window Defogger Inoperative

4
  1. Press and release the defogger switch once.
  2. Wait 15 seconds.
  3. Press and release the defogger switch a second time, before a time-out occurs.
    • The defogger indicator illuminates.
    • The defoggers turn on.
    • The defogger indicator and the defoggers turn off immediately when the switch is pressed the second time.

Rear Window Defogger Inoperative

5
  1. Turn on the radio.
  2. Press and release the defogger switch once.
  3. Wait 15 seconds.
  4. Press and release the defogger switch a second time, before a time-out occurs.

The radio plays normally.

Rear Window Defogger Inoperative

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