Circuit Description
WARNING: This page is about a different car, the 2002 GMC Safari and 2002 Chevrolet Astro. However, it is still accessible from the selected car via links, so may be relevant.
The body control module (BCM) monitors the instrument panel (IP) dimming voltage on the instrument panel lamp fuse supply voltage 2 circuit from the dimmer switch, or thumb wheel, part of the headlamp and panel dimmer switch. The dimmer switch controls the IP dimming by sending a signal to the BCM on the instrument panel lamp fuse supply voltage 2 circuit in order to indicate the position of the thumb wheel when the headlamps are ON. The dimmer switch also provides dimming for the backlighting of the instrument cluster, radio and the overhead console.