GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Astro - 2WD 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Interior Lights Dimming System Check

Step

Action

Normal Result(s)

Abnormal Result(s)*

1
  1. Turn the instrument panel dimmer switch to the OFF position.
  2. Turn the headlamp switch to the PARK position.

The following lamps are all in the ON position:

    • The radio control switches
    • The instrument panel lamp dimmer switch
    • The door lock switches
    • The window switches
    • The heater and A/C control
    • The instrument cluster
    • The instrument panel ashtray flood lamp
    • The automatic transaxle control position indicator

All of the vacuum fluorescent (VF) displays (instrument cluster (SEO) and radio) step dim.

2

Turn the instrument panel lamp dimmer switch slowly to HIGH
  1. The brightness of the instrument panel lamps slowly increase to high.
  2. The VF brightness of the instrument cluster (SEO) and radio slowly increase.

3
  1. Turn the instrument panel lamp dimmer switch to the OFF position.
  2. Turn the park lamp switch to the OFF position.
    • The instrument panel lamps turn OFF.
    • The instrument cluster (SEO) and radio lights turn OFF.

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