Front Fog Lamps

WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

The front fog lamp switch is integral to the left multi-function switch/Steering Control Module (SCM), which communicates with the Body Control Module (BCM). The BCM communicates or broadcasts to the ElectroMechanical Instrument Cluster (EMIC)/Cab Compartment Node (CCN) over the CAN-B. Before performing any of the following tests, determine whether the other functions of the left multi-function switch/SCM are operational. If the other left multi-function switch/SCM functions are ineffective, diagnose and repair that problem before attempting to repair the Front Fog Lamps.

If the BCM receives a short or open circuit from the fog lamp switch, the BCM will set a DTC for each present faulted condition. If the BCM received an open or short circuit while the front fog lamps are ON then the BCM will retain the last state of the fog lamp switch until the next engine cycle. After the next ignition cycle if the headlamp switch is still faulted, the BCM will not activate the front fog lamps.

If the front fog lamp switch is active for 20 second or more, the BCM shall activate the front fog lamps and will set a front fog stick switch fault DTC. If the front fog lamp switch remains faulted, the BCM will continue to drive the front fog lamps in a normal manner until the switch is repaired or replaced. If the front fog switch is no longer stuck, the BCM will clear the related fault DTC.

If the BCM received a front fog command and the PROXI is not correct or set for the vehicle being equipped with fog lamps, the BCM will set a misbuild fault. Run PROXI configuration first.

CONDITION	POSSIBLE CAUSES	CORRECTION
FRONT FOG LAMP DOES NOT ILLUMINATE	1. Ineffective or missing bulb.	1. Test and replace front fog lamp bulb if required.
	2. Ineffective ground circuit.	2. Test and repair open front fog lamp ground circuit if required.
	3. Ineffective feed circuit.	3. Test and repair open front fog lamp feed circuit if required.
	4. Ineffective EMIC (CCN) inputs or outputs.	4. Use a diagnostic scan tool and the appropriate diagnostic information for further EMIC diagnosis.
	5. Ineffective BCM inputs or outputs.	5. Use a diagnostic scan tool to test the BCM inputs and outputs. Refer to the appropriate diagnostic information.
FRONT FOG LAMP DOES NOT EXTINGUISH	1. Ineffective feed circuit.	1. Test and repair shorted front fog lamp feed circuit if required.
	2. Ineffective EMIC (CCN) inputs or outputs.	2. Use a diagnostic scan tool and the appropriate diagnostic information for further EMIC diagnosis.
	3. Ineffective BCM inputs or outputs.	3. Use a diagnostic scan tool to test the BCM inputs and outputs. Refer to the appropriate diagnostic information.