Principles of Operation

The Front Lighting Control Module (FLM) monitors the fog lamp switch and sends a message over the High Speed Controller Area Network (HS-CAN) to the Body Control Module (BCM) to indicate the fog lamp request.

The fog lamps can be turned on when the following conditions are met:

• the ignition is in RUN
• the low beam headlamps or the parking lamps are on
• the high beams are off

When the BCM  receives an input from the FLM  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.