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Principles Of Operation




Fog Lamps

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 (Body Control Module) receives an input from the FLM (Front Lighting Control Module) indicating a request for the fog lamps, the BCM (Body Control Module) provides ground to the fog lamp relay (integrated into the BCM (Body Control Module)). When the fog lamp relay is energized, voltage is routed to the fog lamps.