Principles of Operation
WARNING: This page is about a different car, the 2012 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The Steering Column Control Module (SCCM) monitors the fog lamp switch (integrated into the headlamp switch) and sends a message to the Body Control Module (BCM) over the High Speed Controller Area Network (HS-CAN), indicating the fog lamp switch position.
The fog lamps can be turned on when the following conditions are met:
- The ignition is in RUN or START
- The low beam headlamps or the parking lamps are on
- The high beams are off
When the BCM receives an input from the headlamp switch indicating a request for the fog lamps, the BCM provides ground to the fog lamp relay (integrated into the BCM). When the fog lamp relay is energized, voltage is routed to the fog lamps.