Pinpoint Test M: One Turn Signal/Hazard Lamp Is Inoperative/Always On

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

M1 CHECK THE STOPLAMP
- Apply and release the brake pedal while observing the stoplamp.
- Do the stoplamp operate correctly?
1. YES : Go to M2.
2. NO : REFER to Stoplamp in this.
M2 DETERMINE IF A TURN LAMP IS ALWAYS ON
- Key in ON position.
- Monitor the turn lamps.
- Is either front turn lamp always on?
1. YES : Go to M3.
2. NO : Go to M4.
M3 CHECK CIRCUIT CLS21 (BU/GN) (LH TURN) OR CIRCUIT CLS25 (YE/VT) (RH TURN) FOR A SHORT TO VOLTAGE
- Key in OFF position.
- Disconnect: SJB C2280f
- Key in ON position.
- Does the front turn lamp in question continue to illuminate?
1. YES : For the LH front turn lamp, REPAIR circuit CLS21 (BU/GN). CLEAR the DTCs. REPEAT the self-test.
  For the RH front turn lamp, REPAIR circuit CLS25 (YE/VT). CLEAR the DTCs. REPEAT the self-test.
2. NO : Go to M11.
M4 USE THE RECORDED DTCs FROM THE SJB SELF-TEST
- Check the recorded results from the SJB on-demand self-test.
- Was DTC B2A28 or B2A2A present?
1. YES : Go to M5.
2. NO : Go to M7.
M5 CHECK THE BULB HOLDER FOR A SHORT TO GROUND
- Disconnect: Inoperative Front Turn Lamp
- Enter the following diagnostic mode on the diagnostic tool: SJB Self-Test
- Repeat the SJB on-demand self-test.
- Is DTC B2A28 or B2A2A still present?
1. YES : Go to M6.
2. NO : INSTALL a new bulb holder. TEST the system for normal operation.
M6 CHECK CIRCUIT CLS21 (BU/GN) (DTC B2A2A) OR CIRCUIT CLS25 (YE/VT) (DTC B2A28) FOR A SHORT TO GROUND
- Key in OFF position.
- Disconnect: SJB C2280f
- Measure the resistance between the SJB C2280f-21 (DTC B2A2A), circuit CLS21 (BU/GN), harness side and ground; or between the SJB C2280f-23 (DTC B2A28), circuit CLS25 (YE/VT), harness side and ground.
- Is the resistance greater than 10,000 ohms?
1. YES : Go to M11.
2. 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.

M7 CHECK THE GROUND CIRCUIT FOR AN OPEN

NOTE: Make sure the headlamps operate correctly before continuing with diagnostics for the turn lamps.

Key in OFF position.
Disconnect: Inoperative Turn Lamp

Fig 2: Measuring Resistance Between Inoperative Turn Lamp, Harness Side & Ground

Courtesy of FORD MOTOR CO.

Measure the resistance between the inoperative turn lamp, harness side and ground as follows

Inoperative Turn Lamp	Connector-Pin	Circuit
Edge
LH front	C1023-1	GD123 (BK/GY)
RH front	C1043-1	GD120 (BK/GN)
MKX
LH front headlamp	C1021a-6	GD123 (BK/GY)
RH front headlamp	C1041a-6	GD123 (BK/GY)

Is the resistance less than 5 ohms?

YES : Go to M9.
NO : For MKX, REPAIR the ground circuit in question for an open. CLEAR the DTCs. REPEAT the self-test.
For Edge LH front turn lamp, REPAIR circuit GD123 (BK/GY) for an open. CLEAR the DTCs. REPEAT the self-test.

For the Edge RH front turn lamp, go to M8.

M8 CHECK CIRCUIT GD120 (BK/GN) FOR AN OPEN
- Disconnect: Joint Connector 7 C2200
- Measure the resistance between the RH front turn lamp C1043-1, circuit GD120 (BK/GN), harness side and the joint connector 7 C2200-C, 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.

M9 CHECK FOR VOLTAGE TO THE TURN LAMP

Connect: SJB C2280e
Turn the hazard lamps on.

Fig 4: Measuring Resistance Between Inoperative Turn Lamp, Harness Side & Ground

Courtesy of FORD MOTOR CO.

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

Inoperative Turn Lamp Connector-Pin	Circuit
Edge
LH front C1023-3	CLS21 (BU/GN)
RH front C1043-3	CLS25 (YE/VT)
MKX
LH front headlamp C1021a-5	CLS21 (BU/GN)
RH front headlamp C1041a-5	CLS25 (YE/VT)

Does the voltage alternate from 0 volts to greater than 10 volts?

YES : For Edge, INSTALL a new bulb holder. CLEAR the DTCs. REPEAT the self-test.
For MKX, REPAIR or INSTALL a new headlamp. REFER to Headlamp Assembly in this. CLEAR the DTCs. REPEAT the self-test.
NO : Go to M10.

M10 CHECK CIRCUIT CLS21 (BU/GN) (LH TURN) OR CIRCUIT CLS25 (YE/VT) (RH TURN) FOR AN OPEN

Disconnect: SJB C2280f

Fig 5: Measuring Resistance Between Inoperative Turn Lamp, Harness Side & SJB

Courtesy of FORD MOTOR CO.

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

Inoperative Turn Lamp Connector-Pin	SJB Connector-Pin	Circuit
Edge
LH front C1023-3	C2280f-21	CLS21 (BU/GN)
RH front C1043-3	C2280f-23	CLS25 (YE/VT)
MKX
LH front headlamp C1021a-5	C2280f-21	CLS21 (BU/GN)
RH front headlamp C1041a-5	C2280f-23	CLS25 (YE/VT)

Is the resistance less than 5 ohms?

YES : Go to M11.
NO : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test

M11 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.