Pinpoint Test B: One Low Beam Headlamp Is Inoperative

WARNING: This page is about a different car, the 2007 Lincoln MKX and 2007 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

NOTE: Due to varying wattage ratings and resulting current draw, certain aftermarket headlamp bulbs may cause the SJB to shut down the short circuit protection, resulting in the low beams becoming inoperative. Verify that the bulbs meet Ford specifications. If the bulbs do not meet Ford specifications, install the correct bulbs. Run the on-demand self-test (required to clear certain DTCs and reset the SJB). Correct any unresolved DTCs. Clear all DTCs. Test the system for normal operation.

NOTE: The battery ground cable must be disconnected for accurate test results when checking ground circuits for continuity to ground.

B1 USE THE RECORDED DTCs FROM THE SJB SELF-TEST
- Check the recorded results from the SJB self-test.
- Is DTCs B2A2F or B2A31 recorded?
1. YES : For MKX, go to B7.
  For Edge, go to B8.
2. NO : Go to B2.

B2 CHECK THE HEADLAMP GROUND CIRCUIT FOR CONTINUITY TO GROUND

Key in OFF position.
Disconnect: Inoperative Headlamp

Fig 1: Measuring Resistance Between Inoperative Headlamp, Harness Side & Ground

Courtesy of FORD MOTOR CO.

Measure the resistance between the inoperative headlamp, harness side and ground as follows:

Connector-Pin	Circuit
Edge
LH low beam C1111-A	GD120 (BK/GN)
RH low beam C1112-A	GD123 (BK/GY)
MKX
LH headlamp C1021a-2	GD120 (BK/GN)
RH headlamp C1041a-2	GD123 (BK/GY)

Is the resistance less than 5 ohms?

YES :
For MKX, go to B5.

For Edge, VERIFY the SJB fuse 7 (10A) (LH low beam) or fuse 8 (10A) (RH low beam) is OK. If OK Go to B6.
NO : For RH headlamp, REPAIR circuit GD123 (BK/GY) for an open. CLEAR the DTCs. REPEAT the self-test.
For LH headlamp, go to B3.

B3 CHECK CIRCUIT GD120 (BK/GN) FOR AN OPEN (JOINT CONNECTOR TO GROUND)
- Disconnect: Joint Connector 7 C2200
- Measure the resistance between the joint connector 7 C2200-J, circuit GD120 (BK/GN), harness side and ground.
- Is the resistance less than 5 ohms?
1. YES : Go to B4.
2. NO : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
B4 CHECK CIRCUIT GD120 (BK/GN) FOR AN OPEN (HEADLAMP TO JOINT CONNECTOR)
- For Edge, measure the resistance between the LH low beam C1111-A, circuit GD120 (BK/GN), harness side and the joint connector 7 C2200-E, circuit GD120 (BK/GN), harness side.
- For MKX, measure the resistance between the LH headlamp C1021a-2, circuit GD120 (BK/GN), harness side and the joint connector 7 C2200-A, circuit GD120 (BK/GN), harness side.
- Is the resistance less than 5 ohms?
1. YES : INSTALL a new joint connector. CLEAR the DTCs. REPEAT the self-test.
2. NO : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

B5 CHECK THE SJB HEADLAMP VOLTAGE SUPPLY CIRCUIT FOR VOLTAGE

Place the headlamp switch in the HEADLAMPS ON position.

Fig 5: Measuring Voltage Between Inoperative Headlamp, Harness Side & Ground

Courtesy of FORD MOTOR CO.

Measure the voltage between the inoperative headlamp, harness side and ground as follows:

Connector-Pin	Circuit
LH headlamp C1021a-1	CLF04 (BN/BU)
RH headlamp C1041a-1	CLF05 (BU/GN)

Is the voltage greater than 10 volts?

YES : REPAIR or INSTALL a new headlamp assembly. REFER to Headlamp Assembly in this. CLEAR the DTCs. REPEAT the self-test.
NO : VERIFY the SJB fuse 7 (10A) (LH low beam) or fuse 8 (10A) (RH low beam) is OK. If OK, go to B6.

B6 CHECK THE SJB HEADLAMP VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Place the headlamp switch in the OFF position.
Disconnect: SJB C2280e

Fig 6: Measuring Resistance Between Inoperative Headlamp, Harness Side & SJB

Courtesy of FORD MOTOR CO.

Measure the resistance between the inoperative headlamp, harness side and the SJB as follows:

Headlamp Connector-Pin	SJB Connector-Pin	Circuit
Edge
LH low beam C1111-B	SJB C2280e-13	CLF04 (BN/BU)
RH low beam C1112-B	SJB C2280e-4	CLF05 (BU/GN)
MKX
LH headlamp C1021a-1	SJB C2280e-13	CLF04 (BN/BU)
RH headlamp C1041a-1	SJB C2280e-4	CLF05 (BU/GN)

Is the resistance less than 5 ohms?

YES : Go to B9.
NO : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.

B7 CHECK THE HEADLAMP ASSEMBLY
- Key in OFF position.
- Disconnect: Inoperative Headlamp
- Key in ON position.
- Repeat the SJB on-demand self-test.
- Is DTC B2A2F or B2A31 retrieved again?
1. YES : Go to B8.
2. NO : INSTALL a new headlamp assembly. REFER to Headlamp Assembly in this. TEST the system for normal operation.

B8 CHECK CIRCUIT CLF04 (BN/BU) (LH HEADLAMP) OR CIRCUIT CLF05 (BU/GN) (RH HEADLAMP) FOR A SHORT TO GROUND

Key in OFF position.
Disconnect: SJB C2280e
Disconnect: Inoperative Headlamp

Fig 7: Measuring Resistance Between Inoperative Headlamp, Harness Side & Ground

Courtesy of FORD MOTOR CO.

Measure the resistance between the inoperative headlamp, harness side and ground as follows:

Connector-Pin	Circuit
Edge
LH low beam C1111-B	CLF04 (BN/BU)
RH low beam C1112-B	CLF05 (BU/GN)
MKX
LH headlamp C1021a-1	CLF04 (BN/BU)
RH headlamp C1041a-1	CLF05 (BU/GN)

Is the resistance greater than 10,000 ohms?

YES : Go to B9.
NO : REPAIR the circuit in question. RUN the on-demand self-test (required to clear certain DTCs). CORRECT any unresolved DTCs. CLEAR all DTCs. TEST the system for normal operation.

B9 CHECK FOR CORRECT SJB OPERATION
- Disconnect all the SJB connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the SJB connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
1. YES : INSTALL a new SJB. REFER to MULTIFUNCTION ELECTRONIC MODULES . TEST the system for normal operation.
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.