Interior Lamps Dimming

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 third group includes lamps which may be dimmed. This group may use a combination of vacuum fluorescent (VF) illumination and incandescent lamps.

HVAC control head assembly
Radio and remote CD player
Instrument panel cluster (IPC)
Rear window wiper/washer switch
Rear heater switch
Rear A/C switch
Rear audio controls
Overhead driver information display module

When the ignition switch is turned to the ON position, the radio and driver information display module vacuum fluorescent (VF) displays turn on at maximum brightness. When the park lamps are on, all incandescent backlighting turn on at the dimming level indicated by the IP dimmer switch. At the same time, all vacuum fluorescent (VF) displays are controlled by the BCM to match the indicated IP dimmer switch dimming level. Battery positive voltage is supplied from the PK LPS fuse in the IP fuse block to the headlamp and panel dimmer switch and to the ILLUM fuse also located in the IP fuse block. The IP panel dimmer switch potentiometer receives both its voltage and ground from the headlamp switch and is also an input to the BCM. When the driver selects a dimming setting by moving the IP dimming switch potentiometer, all incandescent backlighting lamps are provided with a specific voltage. The incandescent backlighting lamps are then grounded at G105, G107, G110 and G200. When the IP dimmer switch is moved from MIN to MAX, all vacuum fluorescent (VF) displays, as well as all incandescent backlighting respond from minimum intensity to maximum brightness in response to the IP dimmer switch.