Rear Fog Lamps

Vehicles equipped with optional rear fog lamps include a rear fog lamp switch integral to the headlamp switch on the instrument panel. The rear fog lamps have a path to ground at all times through their connection to the body wire harness and a takeout with an eyelet terminal that is secured to the body sheet metal. The Body Control Module (BCM) monitors a hard wired multiplex input from the headlamp switch to determine whether the fog lamps are selected.

When the BCM input from the headlamp switch indicates the rear fog lamps are selected, it controls rear fog lamp operation by providing a battery voltage output to the fog lamps through the right and left rear fog lamp control circuits. The BCM also sends the appropriate electronic messages to the Instrument Cluster (IC) to illuminate or extinguish the rear fog lamp indicator.

The BCM will only allow the rear fog lamps to operate while the front fog lamps are also selected. Refer to SWITCH, HEADLAMP, OPERATION .