Test No. 7: Brightness Does Not Change Even When Rheostat Is Turned

WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

Remove and inspect suspect light bulb. Replace light bulb as required. After repairs have been made, perform confirmation test. See CONFIRMATION TEST . If light bulb is okay, go to next step.
Turn ignition off. Remove light control rheostat. Light control rheostat is incorporated into heating and ventilation register on left side of instrument panel. Disconnect 3-pin electrical harness connector from rheostat. Remove instrument cluster 22-pin electrical harness connector C9 and multi-display information center 22-pin electrical harness connector M3. See Figure. Check White/Green wire between light control rheostat 3-pin electrical harness connector terminal No. 2, instrument cluster 22-pin electrical harness connector C9 terminal A19 and multi-display information center 22-pin electrical harness connector M3 terminal A10. See INTERIOR LIGHTS in SYSTEM WIRING DIAGRAMS article. If circuit is faulty, repair and retest system. If circuit is okay, replace instrument cluster and/or multi-display information center. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .