Principles Of Operation
Parking, Rear and License Plate Lamps
Principles of Operation
The headlamp switch is integrated into the Front Lighting Control Module (FLM). The FLM (Front Lighting Control Module) monitors the headlamp switch position and sends a message over the High Speed Controller Area Network (HS-CAN) to the Body Control Module (BCM) to indicate the headlamp switch status (position or a fault with the headlamp switch).
If the BCM (Body Control Module) detects a fault from the headlamp switch or loses communication with the FLM (Front Lighting Control Module), the BCM (Body Control Module) turns the parking lamps and headlamps on and keeps them on until the battery saver feature times out.
Refer to Exterior Lighting Exterior Lighting in the Description and Operation for information regarding the battery saver feature.
If either situation occurs, the BCM (Body Control Module)cannot be ruled immediately as being at fault. This is normal behavior of the BCM (Body Control Module) design as a fault has been detected with the inputs from the headlamp switch.
When the BCM (Body Control Module) receives input requesting the parking lamps on, it energizes an internal relay to provide voltage to the parking lamps.