Circuit Description
WARNING: This page is about a different car, the 2002 Buick Regal and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
The Body Control Module (BCM) uses the ambient light sensor signal to control the automatic headlamp control system and the Daytime Running Lamps (DRL). The ambient light sensor is connected directly to the BCM through the DRL ambient light sensor signal circuit and the DRL ambient light low reference circuit.