Circuit Description
WARNING: This page is about a different car, the 2003 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
The ambient light sensor circuit provides an input to the BCM for DRL and automatic headlight functions. This input allows the BCM to activate or deactivate DRL and automatic headlamps with different ambient light levels. The BCM supplies a 5 volt reference circuit and a signal circuit to the ambient light sensor. The BCM will detect high voltage on the ambient light sensor signal circuit when ambient light is high, and low voltage when ambient light is low. The BCM monitors the ambient light sensor voltage at the signal circuit and determines if the voltage is within range. If the voltage is not within range, a malfunction is present and a DTC will set.