Circuit Description
WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
The body control module (BCM) supplies voltage to the instrument panel (I/P) dimmer switch through the I/P dimmer switch signal circuit. The dimmer switch varies the voltage and returns the new voltage to the BCM through the dimmer switch signal return circuit. The BCM uses this voltage to determine the illumination level of the I/P lamps.