The dimmer switch controls the brightness of the incandescent lamps and vacuum fluorescent (VF) displays.

Incandescent Dimming

The brightness of the incandescent lamps is determined by a variable voltage signal produced by circuit 8 from the dimmer switch.

Vacuum Fluorescent (VF) Dimming

When the park lamps are turned on, the VF dimming signal (circuit 32) is applied to the radio, heater and the A/C control, and the instrument cluster dimming these components for night time viewing.