Circuit Operation - Interior Lights Dimming

The I/P dimmer switch controls the brightness of the incandescent lamps and Vacuum Fluorescent (VF) displays. The incandescent lamps are located in various components (see schematics) and the VF displays are located in the radio.

Incandescent Dimming
The brightness of the incandescent lamps is determined by a variable voltage signal produced by the I/P dimmer switch.

Vacuum Fluorescent (VF) Dimming
The brightness of the Vacuum Fluorescent (VF) displays is controlled by the VF dimming signal. With the park lamps on, the VF display of the radio will dim for low light viewing. When the park lamps on signal is not present (park lamps off), the VF displays are at high brightness for daytime viewing. When the park lamps are on, the I/P lamp dimmer switch provides a signal (VF Dimming Signal circuit 230) which controls the brightness of the VF displays when the I/P dimmer switch is adjusted.

Park Lamp Dimming
When the park lamps are turned on, the park lamps on signal (circuit 308) is applied to the radio, heater and A/C control (CJ2), trip calculator and instrument cluster dimming these components for night time viewing.