Pinpoint Test E : The Rear Fog Lamp Is On Continuously

WARNING: This page is about a different car, the 2020 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.

E1 CHECK THE HEADLAMP SWITCH
- Ignition OFF.
- Disconnect: Headlamp Switch C205.
- Carry out the headlamp switch component test. Refer to Component Testing for schematic and connector information.
Does the headlamp switch pass the component test?

Yes GO to E2

No INSTALL a new headlamp switch. REFER to: Headlamp Switch .

E2 CHECK THE REAR FOG LAMP SWITCH CIRCUIT FOR A SHORT TO GROUND

Disconnect: BCM C2280B.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C205-2	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance greater than 10, 000 ohms?

Yes

GO to E3

No	REPAIR the circuit.

E3 CHECK THE REAR FOG LAMP VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect: BCM C2280C.
- Ignition ON.
Does the rear fog lamp continue to illuminate?

Yes REPAIR the circuit.

No GO to E4

E4 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION

Disconnect and inspect all BCM and all related in-line connectors.

Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary

Reconnect the BCM and all related in-line connectors. Make sure they seat and latch correctly.

Operate the system and determine if the concern is still present.

Is the concern still present?

Yes	CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, Refer to BCM GUIDED ROUTINE .

No	The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.