Pinpoint Test D : The Rear Fog Lamp Is Inoperative

WARNING: This page is about a different car, the 2015 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.

D1 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 D2

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

D2 CHECK THE HEADLAMP SWITCH FOG LAMP ENABLE CIRCUIT FOR AN OPEN

Disconnect: BCM C2280B .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C205-2	Courtesy of FORD MOTOR COMPANY	C2280B-8

Is the resistance less than 3 ohms?

Yes

GO to D3

No	REPAIR the circuit.

D3 CHECK FOR VOLTAGE TO THE REAR FOG LAMP

Connect: Headlamp Switch C205 .

Connect: BCM C2280C .

Disconnect: Rear Fog Lamp C436.

Ignition ON.

Place the headlamp switch in the PARKING LAMPS position and engage the rear fog lamp switch.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C436-1	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 11 volts?

Yes

GO to D5

No	GO to D4

D4 REPEAT THE ON-DEMAND SELF-TEST AND CHECK FOR VOLTAGE TO THE REAR FOG LAMP

Disengage the rear fog lamp switch and place the headlamp switch in the OFF position.

Using a diagnostic scan tool, perform the BCM self-test.

Clear the Diagnostic Trouble Codes (DTCs) and repeat the self-test (required to enable the lamp output driver if DTC U1000:00 is present).

Ignition OFF.

Ignition ON.

Place the headlamp switch in the PARKING LAMPS position and engage the rear fog lamp switch.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C436-1	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 11 volts?

Yes	INSTALL a new rear fog lamp

No	GO to D6

D5 CHECK REAR FOG LAMP GROUND CIRCUIT FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C436-1	Courtesy of FORD MOTOR COMPANY	C436-2

Is the voltage greater than 11 volts?

Yes	INSTALL a new rear fog lamp.

No	REPAIR the circuit.

D6 CHECK REAR FOG LAMP VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO GROUND

Place the headlamp switch in the OFF position.

Ignition OFF.

Disconnect: BCM C2280C .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C436-1	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance greater than 10, 000 ohms?

Yes

GO to D7

No	REPAIR the circuit. After the repair: If no Diagnostic Trouble Codes (DTCs) are present, TEST the system for normal operation. If DTC U1000:00 is present, CLEAR the Diagnostic Trouble Codes (DTCs) and REPEAT the self-test (required to enable the lamp output driver if DTC U1000:00 is present). If DTC U3000:49 is present, Refer to BCM Hardware Testing .

D7 CHECK REAR FOG LAMP VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C436-1	Courtesy of FORD MOTOR COMPANY	C2280C-25

Is the resistance less than 3 ohms?

Yes

GO to D8

No	REPAIR the circuit.

D8 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 Hardware Testing .

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.