Radio Incandescent Dimming
WARNING: This page is about a different car, the 2003 Pontiac Montana, 2003 Oldsmobile Silhouette, and 2003 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.
The radio has both in candescent lamps and vacuum fluorescent VF dimming. The brightness of the radio incandescent lamps is determined by a variable voltage signal produced by the dimmer switch and sent through the instrument panel lamps dimming control circuit. The instrument panel lamps dimming control circuit is exclusive to the radio incandescent lamps.