Ambient Light Sensor
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2000 GMC Yukon XL, 2000 GMC Yukon, 2000 GMC Sierra, 2000 Chevrolet Tahoe, and 2000 Chevrolet Suburban. However, it is still accessible from the selected car via links, so may be relevant.
The ambient light sensor has 2 states: light and dark. When headlight switch is in AUTO position while in the light state, the radio, PRNDL display and passenger air bag switch will stay fully bright. If headlight switch is in PARK LAMP or HEADLAMP position while in the light state, the radio, PRNDL display and passenger air bag switch will dim with dimming control. If headlight switch is in AUTO, PARK LAMP or HEADLAMP position while in dark state, the radio, PRNDL display and 4-wheel drive switch will dim with dimming control.