Interior Lamps Dimming

WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

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

The door switches and the window switches
The HVAC control head assembly
The radio
The instrument panel cluster (IPC)
The steering wheel controls
The heated seat switch
The HUD switch
The lift glass window release switch and traction control switch

When the ignition switch is turned to the ON position, the vacuum fluorescent (VF) displays (radio and HVAC control assembly), incandescent lamps, turn on at maximum brightness. When the park lamps are on and the ambient light sensor indicates low light conditions, all incandescent back lighting turn on at the dimming level indicated by the IP dimmer switch. At the same time all vacuum fluorescent (VF) displays dim to match the indicated dimming level. The BCM L fuse in the console fuse block, supplies battery positive voltage to the BCM. The I/P courtesy lamps supply voltage circuit of the BCM, supplies battery positive voltage to all the dimmable lamps. When the headlamp switch is placed in the PARK position, the BCM will then dim the interior lamps to the dimming level indicated by the IP dimmer switch. When the driver selects a dimming setting by moving, the IP dimming switch potentiometer, all incandescent back lighting lamps are provided with a specific voltage. The incandescent back lighting lamps are then grounded at G200, G301 and G302. When the IP dimmer switch is moved from MIN to MAX, all vacuum fluorescent (VF) displays, as well as all incandescent back lighting respond from Minimum intensity to maximum brightness in response to the IP dimmer switch.

The driver may select parade mode by manually turning on the park lamps during daylight conditions. The front park lamp circuit supplies voltage to the instrument panel cluster, radio and HVAC assembly for a park lamp on input, and the displays will become full bright.