GM Service Manual Online
For 1990-2009 cars only

Step

Action

Normal Result(s)

Abnormal Result(s)*

1

    • Turn the ignition switch to the RUN position.
    • Press the rear defogger switch.

The rear defogger LED will light, and both the grid and the outside mirrors will get warm. After approximately 10 minutes the system will turn OFF.

    • Indicator does not light, the grid does not warm.
    • Indicator lights, the grid does not warm.

2

    • Turn the ignition switch to the RUN position.
    • Press the rear defogger switch.

The outside mirrors will get warm.

Outside mirrors do not warm.