Pinpoint Test N: The Brake Warning Indicator Is Never/Always On - 2.3L Only

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

N1 CHECK THE OPERATION OF THE INSTRUMENT CLUSTER

Key in OFF position.
Connect the diagnostic tool.
Key in ON position.
Enter the following diagnostic mode on the diagnostic tool: Instrument Cluster Active Command.
Select the instrument cluster active command ALL LAMPS ON and OFF.
Does the brake warning indicator illuminate and turn off?

Yes

If the brake warning indicator is never on, GO to N2.

If the brake warning indicator is always on, GO to N7.

GO to N13.

N2 CHECK THE PARKING BRAKE SWITCH

Key in OFF position.
Disconnect: Parking Brake Switch C2015.
Measure the resistance between the parking brake switch C2015 pin 1, circuit 31S-GE44 (BK/RD), component side and ground while applying and releasing the parking brake.

Fig 1: Checking Parking Brake Switch
Courtesy of FORD MOTOR CO.
Is the resistance less than 5 ohms with the parking brake applied and greater than 10,000 ohms with the parking brake released?

Yes

GO to N3.

INSTALL a new parking brake switch. TEST the system for normal operation.

N3 CHECK CIRCUIT 31S-GE44 (BK/RD) FOR OPEN

Disconnect: Instrument Cluster C2220.
Measure the resistance between the instrument cluster C2220 pin 22, circuit 31S-GE44 (BK/RD), harness side and the parking brake switch C2015 pin 1, circuit 31S-GE44 (BK/RD), harness side.

Fig 2: Checking Circuit 31S-GE44 (BK/RD) For Open
Courtesy of FORD MOTOR CO.
Is the resistance less than 5 ohms?

Yes

GO to N4.

REPAIR the circuit. TEST the system for normal operation.

N4 CHECK CIRCUIT 31S-GE44 (BK/RD) FOR SHORT TO POWER

Key in ON position.
Measure the voltage between the instrument cluster C2220 pin 22, circuit 31S-GE44 (BK/RD), harness side and ground.

Fig 3: Checking Circuit 31S-GE44 (BK/RD) For Short To Power
Courtesy of FORD MOTOR CO.
Is any voltage present?

Yes

REPAIR the circuit. TEST the system for normal operation.

GO to N5.

N5 CHECK THE BRAKE FLUID LEVEL SWITCH

Key in OFF position.
Disconnect: Brake Fluid Level Switch C124.
Connect a fused (5A) jumper wire between the brake fluid level switch C124 pin 2, circuit 31S-GC6 (BK/YE), harness side and ground.

Fig 4: Checking Brake Fluid Level Switch
Courtesy of FORD MOTOR CO.
Key in ON position.
Does the brake warning indicator illuminate?

Yes

GO to N6.

REPAIR circuit 31S-GC6 (BK/YE). TEST the system for normal operation.

N6 CHECK CIRCUIT 91-GC7 (BK/BU) FOR OPEN

Key in OFF position.
Measure the resistance between the brake fluid level switch C124 pin 1, circuit 91-GC7 (BK/BU), harness side and ground.

Fig 5: Checking Circuit 91-GC7 (BK/BU) For Open
Courtesy of FORD MOTOR CO.
Is the resistance less than 5 ohms?

Yes

INSTALL a new brake fluid level switch. TEST the system for normal operation.

REPAIR the circuit. TEST the system for normal operation.

N7 VERIFY THE PARKING BRAKE SWITCH OPERATION

Key in OFF position.
Disconnect: Parking Brake Switch C2015.
Key in ON position.
Check the operation of the brake warning indicator.
Does the brake warning indicator turn off?

Yes

INSTALL a new parking brake switch. TEST the system for normal operation.

GO to N8.

N8 VERIFY THE BRAKE FLUID LEVEL SWITCH OPERATION

NOTE: Make sure that the brake fluid level is full prior to carrying out this test step.

Disconnect: Brake Fluid Level Switch C124.
Key in ON position.
Measure the resistance of the brake warning switch C124 pin 2, circuit 31S-GC6 (BK/YE), component side and the brake warning switch C124 pin 3, circuit 91-GC7 (BK/BU), component side.

Fig 6: Verifying The Brake Fluid Level Switch Operation
Courtesy of FORD MOTOR CO.
Is the resistance greater than 10,000 ohms?

Yes

INSTALL a new brake fluid level switch. TEST the system for normal operation.

GO to N9.

N9 CHECK CIRCUIT 31S-GE44 (BK/RD) FOR A SHORT TO GROUND

Key in OFF position.
Disconnect: Instrument Cluster C2220.
Measure the resistance between the parking brake switch C2015 pin 1, circuit 31S-GE44 (BK/RD), harness side and ground.

Fig 7: Checking Circuit 31S-GE44 (BK/RD) For A Short To Ground
Courtesy of FORD MOTOR CO.
Is the resistance greater than 10,000 ohms?

Yes

GO to N10.

REPAIR the circuit. TEST the system for normal operation.

N10 CHECK CIRCUIT 31S-GC6 (BK/YE) FOR A SHORT TO GROUND

Key in OFF position.
Disconnect: Instrument Cluster C2220.
Measure the resistance between the brake fluid level switch C124 pin 2, circuit 31S-GC6 (BK/YE), harness side and ground.

Fig 8: Checking Circuit 31S-GC6 (BK/YE) For A Short To Ground
Courtesy of FORD MOTOR CO.
Is the resistance greater than 10,000 ohms?

Yes

GO to N11.

REPAIR the circuit. TEST the system for normal operation.

N11 CHECK CIRCUIT 31S-CF45 (BK/GN) FOR AN OPEN

Disconnect: ABS Module C135.
Measure the resistance between the ABS module C135 pin 39, circuit 31S-CF45 (BK/GN), harness side and the instrument cluster C2220 pin 21, circuit 31S-CF45 (BK/GN), harness side.

Fig 9: Checking Circuit 31S-CF45 (BK/GN) For An Open
Courtesy of FORD MOTOR CO.
Is the resistance less than 5 ohms?

Yes

GO to N12.

REPAIR the circuit. TEST the system for normal operation.

N12 CHECK FOR CORRECT ABS MODULE OPERATION

Disconnect all ABS module connectors.
Check for:
- corrosion
- pushed-out pins
Connect all ABS module connectors and make sure they seat correctly.
Operate the system and verify the concern is still present.
Is the concern still present?

Yes

INSTALL a new ABS module. Refer to ANTI-LOCK BRAKE SYSTEM (ABS) MODULE . TEST the system for normal operation.

The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTCs. TEST the system for normal operation.

N13 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION

Disconnect all instrument cluster connectors.
Check for:
- corrosion
- pushed-out pins
Connect all instrument cluster connectors and make sure they seat correctly.
Operate the system and verify the concern is still present.
Is the concern still present?

Yes

INSTALL a new instrument cluster. Refer to INSTRUMENT CLUSTER . TEST the system for normal operation.

The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTCs. TEST the system for normal operation.