System Operation - Autolamps: Autolamps
WARNING: This page is about a different car, the 2018 Lincoln Navigator. However, it is still accessible from the selected car via links, so may be relevant.
The BCM monitors the light sensor with a voltage signal. The light sensor input to the BCM varies with the ambient light conditions.
The BCM monitors the headlamp switch circuits to indicate the headlamp switch position.
When the BCM receives a headlamp switch status indicating a request for the autolamps, the BCM monitors the light sensor for the ambient light condition. If the BCM determines the ambient light level is dark, the BCM illuminates the exterior parking and low beam lamps.