Radio Control Knob/LCD Display Illumination

Radio Control Knob/LCD Display Illumination

The Instrument Panel Dimming Rheostat controls the brightness of the Electronic Radio control knob illumination bulbs, as well as the brightness of the LCD time/frequency display.

With the Ignition Switch in ACC or RUN, voltage is present at the Instrument Panel Dimming Rheostat through the RADIO Fuse and circuit 600 (DB/BK). With the Main Light Switch turned to OFF, the Instrument Panel Dimming Rheostat applies battery voltage at C257, pin D of the Electronic Radio and the LCD display is illuminated at full brightness.

With the Main Light Switch in PARK or HEAD, the Rheostat: 1) reduces voltage to C257, pin D, to reduce LCD display illumination brightness, and 2) applies voltage to C257, pin E, to illuminate the Electronic Radio control knob illumination bulbs.