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. Diagrams By Number
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 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 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 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
PINPOINT TEST A: THE WIPERS ARE INOPERATIVE - WINDSHIELD
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A1 CHECK FOR BCM DTCs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self-Test - BCM.
- Are any BCM DTCs present?
Yes
REFER to the Body Control Module (BCM) DTC Chart for further diagnosis. [1][2]Diagnostic Trouble Code Descriptions
No
GO to A2.
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A2 CHECK THE BCM WINDSHIELD WIPER SWITCH PIDs
- Enter the following diagnostic mode on the scan tool: DataLogger - BCM.
- Monitor the BCM 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.
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A3 CHECK THE WIPER/WASHER SWITCH
- Ignition OFF.
- Disconnect: Wiper/Washer Switch C2081.
- Carry out the wiper/washer switch component test.
Refer to Windshield Washer Switch or Wiper Switch for component testing.
- Does the wiper/washer switch pass the component test?
Yes
GO to A4.
No
INSTALL a new wiper/washer switch. REFER to Steering Column Switches Steering Column Multifunction Switch. TEST the system for normal operation.
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A4 CHECK THE WIPER GROUND CIRCUIT FROM THE BCM
- Disconnect: BCM C2280F.
- Measure the resistance between the wiper/washer switch C2081-5, circuit CRW17 (GN/VT), harness side and BCM 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.
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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.
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A6 CHECK THE BCM VOLTAGE
- Disconnect: BCM C2280B.
- Ignition ON.
- Measure the voltage between BCM C2280B-10, circuit CBP11 (BN), harness side and ground and between BCM 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 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. Diagrams By Number
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. Diagrams By Number
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A7 CHECK THE BCM GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
- Ignition OFF.
- Disconnect: BCM C2280A.
- Measure the resistance between BCM 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.
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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 C2280A-10, circuit CRW15 (BN/WH), harness side and between windshield wiper motor C125-2, circuit CRW16 (GY/BN), harness side and BCM 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.
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A9 CHECK FOR VOLTAGE TO THE WINDSHIELD WIPER MOTOR USING THE BCM PIDs FRONT WIPER RELAY - LOW SPEED (WPR_RLY_F_Lo) AND FRONT WIPER RELAY - FAST SPEED (WPR_RLY_F_Hi)
- Connect: BCM C2280A.
- Connect: BCM C2280B.
- Connect: BCM C2280F (if previously disconnected).
- Connect: Wiper/Washer Switch C2081 (if previously disconnected).
- Ignition ON.
- Command the BCM 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 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.
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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.
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A11 CHECK FOR CORRECT BCM OPERATION
- Ignition OFF.
- Inspect the BCM connectors for the following conditions:
- corrosion
- damaged or pushed out pins
- Connect the BCM 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. REFER to Multifunction Electronic Modules Body Control Module (BCM). 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.
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