Pinpoint Test A: The Wipers Are Inoperative - Windshield

Wipers and Washers

Pinpoint Test A: The Wipers Are Inoperative - Windshield

Refer to Wiring Diagram Set 81, Wipers and Washers for schematic and connector information Electrical Diagrams.

Normal Operation

Power is supplied from the Central Junction Box (CJB) to the Body Control Module (BCM) for the front wiper system when the ignition is in the ON position. The BCM (Body Control Module) supplies a signal voltage(s) to the wiper/washer switch for the HIGH speed, LOW speed, and INTERMITTENT functions. Each function has its own dedicated signal (sense) voltage. The wiper/washer switch physically grounds the signal voltage(s) when a function is selected. The BCM (Body Control Module) then reacts to the grounded signal voltage(s) and its integral electronics make a decision on which wiper system function to carry out. Ground is supplied to the wiper motor through a circuit that is shared by the BCM (Body Control Module) windshield wiper return circuit.

This pinpoint test is intended to diagnose the following:

- Fuse(s)

- Wiring, terminals or connectors

- Windshield wiper motor

- Wiper/washer switch

- BCM (Body Control Module)

PINPOINT TEST A : THE WIPERS ARE INOPERATIVE - WINDSHIELD

A1 CHECK FOR BCM (Body Control Module) DTCs

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: Self-Test- BCM (Body Control Module).

Are any BCM (Body Control Module) DTCs present?

Yes
REFER to the Body Control Module (BCM) DTC Chart for further diagnosis Wiper and Washer Systems.

No
GO to A2.

A2 CHECK THE BCM (Body Control Module) WINDSHIELD WIPER SWITCH PIDs

- Enter the following diagnostic mode on the scan tool: DataLogger- BCM (Body Control Module).

- Monitor the BCM (Body Control Module) PIDs listed below while operating the wiper/washer switch in the INTERMITTENT, LOW and HIGH positions.
- Front Wiper Interval/Auto Wiper Switch (FRNWIPER_Int)

- Front Wiper Command Low Speed (FRNWIPER_Lo)

- Front Wiper Command High Speed (FRNWIPER_Hi)


Does the status of each PID match the wiper/washer switch setting?

Yes
GO to A6.

No
GO to A3.

A3 CHECK THE WIPER/WASHER SWITCH

- Ignition OFF.

- Disconnect: Wiper/Washer Switch C2081.

- Carry out the wiper/washer switch component test.

Does the wiper/washer switch pass the component test?

Yes
GO to A4.

No
INSTALL a new wiper/washer switch. TEST the system for normal operation.

A4 CHECK THE WIPER GROUND CIRCUIT FROM THE BCM (Body Control Module)

- Disconnect: BCM (Body Control Module) C2280F.

- Measure the resistance between the wiper/washer switch C2081-5, circuit CRW17 (GN/VT), harness side and BCM (Body Control Module) C2280F-16, circuit CRW17 (GN/VT), harness side.





Is the resistance less than 5 ohms?

Yes
GO to A5.

No
REPAIR the circuit. TEST the system for normal operation.

A5 CHECK THE WINDSHIELD WIPER MOTOR GROUND FOR AN OPEN OR HIGH RESISTANCE

- Ignition OFF.

- Disconnect: Windshield Wiper Motor C125.

- Measure the resistance between windshield wiper motor C125-4, circuit GD133 (BK), harness side and ground.





Is the resistance less than 5 ohms?

Yes
GO to A6.

No
REPAIR the circuit. TEST the system for normal operation.

A6 CHECK THE BCM (Body Control Module) VOLTAGE

- Disconnect: BCM (Body Control Module) C2280B.

- Ignition ON.

- Measure the voltage between BCM (Body Control Module) C2280B-10, circuit CBP11 (BN), harness side and ground and between BCM (Body Control Module) C2280B-15, circuit CBP13 (GY/BN), harness side and ground.





Are the voltages greater than 10 volts?

Yes
GO to A7.

No
If circuit CBP11 (BN) was less than 10 volts, VERIFY CJB (Central Junction Box) fuse 11 (20A) is OK. If OK, REPAIR circuit CBP11 (BN) for an open or high resistance. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the short to ground Electrical Diagrams.

If circuit CBP13 (GY/BN) was less than 10 volts, VERIFY Central Junction Box (CJB) fuse 13 (15A) is OK. If OK, REPAIR circuit CBP13 (GY/BN) for an open or high resistance. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the short to ground Electrical Diagrams.

A7 CHECK THE BCM (Body Control Module) GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE

- Ignition OFF.

- Disconnect: BCM (Body Control Module) C2280A.

- Measure the resistance between BCM (Body Control Module) C2280A-16, circuit GD156 (BK/VT), harness side and ground.





Is the resistance less than 5 ohms?

Yes
GO to A8.

No
REPAIR the circuit. TEST the system for normal operation.

A8 CHECK WINDSHIELD WIPER MOTOR LOW AND HIGH RELAY OUTPUT CIRCUITS FOR AN OPEN OR HIGH RESISTANCE

- Measure the resistance between windshield wiper motor C125-1, circuit CRW15 (BN/WH), harness side and BCM (Body Control Module) C2280A-10, circuit CRW15 (BN/WH), harness side and between windshield wiper motor C125-2, circuit CRW16 (GY/BN), harness side and BCM (Body Control Module) C2280A-9, circuit CRW16 (GY/BN), harness side.





Are the resistances less than 5 ohms?

Yes
GO to A9.

No
REPAIR the affected circuit. TEST the system for normal operation.

A9 CHECK FOR VOLTAGE TO THE WINDSHIELD WIPER MOTOR USING THE BCM (Body Control Module) PIDs FRONT WIPER RELAY - LOW SPEED (WPR_RLY_F_Lo) AND FRONT WIPER RELAY - FAST SPEED (WPR_RLY_F_Hi)

- Connect: BCM (Body Control Module) C2280A.

- Connect: BCM (Body Control Module) C2280B.

- Connect: BCM (Body Control Module) C2280F (if previously disconnected).

- Connect: Wiper/Washer Switch C2081 (if previously disconnected).

- Ignition ON.

- Command the BCM (Body Control Module) PID WPR_RLY_F_Lo on.

- Measure the voltage between windshield wiper motor C125-2, circuit CRW16 (GY/BN), harness side and ground.





- Command the BCM (Body Control Module) PID WPR_RLY_F_Hi on.

- Measure the voltage between windshield wiper motor C125-1, circuit CRW15 (BN/WH), harness side and ground.





Are the voltages greater than 10 volts?

Yes
GO to A10.

No
GO to A11.

A10 CHECK FOR CORRECT WINDSHIELD WIPER MOTOR OPERATION

- Ignition OFF.

- Inspect windshield wiper motor C125 for the following conditions:
- corrosion

- damaged or pushed out pins


- Connect the windshield wiper motor C125 and make sure it seats correctly.

- Operate the system and verify if the concern is still present.

Is the concern still present?

Yes
INSTALL a new windshield wiper motor. REFER to Wiper Motor - Windshield Wiper Motor - Windshield. TEST the system for normal operation.

No
The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.

A11 CHECK FOR CORRECT BCM (Body Control Module) OPERATION

- Ignition OFF.

- Inspect the BCM (Body Control Module) connectors for the following conditions:
- corrosion

- damaged or pushed out pins


- Connect the BCM (Body Control Module) connectors and make sure they seat correctly.

- Connect: Windshield Wiper Motor C125.

- Operate the system and verify if the concern is still present.

Is the concern still present?

Yes
INSTALL a new BCM (Body Control Module). TEST the system for normal operation.

No
The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.