Instrument Panel Lighting

ELECTRONIC RADIO ILLUMINATION

With the ignition Switch in "ACC" or "RUN", voltage is present at pin B of the Instrument Panel Dimming Module. With the Main Light Switch in "OFF", the Park lamp Relay is not energized and voltage is not present at pin B of the Instrument Panel Dimming Module. With this input information, the Module applies zero volts from pin A to enable the Electronic Radio and Graphics Equalizer displays to be at full brightness for daytime visibility.

If the Main Light Switch is placed in "PARK" or "HEAD", the Park Lamp Relay is energized and voltage is now present at pin B of the Instrument Panel Dimming Module. The Module now applies a voltage signal on circuit 306 (GR/R) to dim the LCD displays. At the same time, the Park Lamp Relay applies voltage to illuminate the Electronic Radio control knobs, making them visible at night.

ALL OTHER ILLUMINATION BULBS

With the Ignition Switch in "ACC" or "RUN", voltage is present at the Instrument Panel Dimming Module through the Park Lamp Relay.

With the Main Light Switch in "PARK" or "HEAD", the Park Lamp Relay is energized and voltage is present at all instrument panel illumination bulbs through circuit 80 (0). A ground signal is present at pin C of the Instrument Panel Dimming Module. The ground side of all Instrument Panel illumination bulbs is tied to circuit 305 (GN/Y) which is controlled by the Instrument Panel Dimming Module. This module allows the current to be varied to the illumination bulbs which controls their brightness.