Windshield Wiper System Malfunction
Windshield Wiper System Malfunction
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The Body Control Module (BCM) controls the wiper motor based on input from the windshield wiper/washer switch. The BCM monitors the wiper/washer switch through two separate signal circuits and a ground circuit. The windshield wiper switch high signal circuit is used to determine high speed wiper operation, the windshield wiper switch low signal is used to determine low speed, intermittent, and mist operation through the use of a resistor ladder, and the windshield washer switch signal circuit is used to determine washer operation. The BCM controls the windshield wiper motor low, high, and intermittent operations through a serial data Local Interconnect Network 1 (LIN) Bus control circuit.
The wiper motor park position is controlled by the BCM and the wiper motor park switch. Once the BCM receives the wiper OFF message from the windshield wiper/washer switch, the BCM sends a serial data message on the LIN 1 Bus circuit to the wiper motor to park. The wipers will cycle one additional time until the BCM receives the wiper motor park switch signal. Once the BCM receives this park switch signal response from the wiper motor park switch, the wiper motor will stop.
Reference Information
Schematic Reference
Wiper/Washer Schematics
Connector End View Reference
Component Connector End Views Hybrid/EV Battery Pack X1 A4
Description and Operation
Wiper/Washer System Description and Operation Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON, S82 Windshield Wiper/Washer Switch in the OFF position, verify the scan tool Windshield Washer Switch parameter is INACTIVE.
• If not the specified value, refer to Washer Malfunction Washer Malfunction.
2. S82 Windshield Wiper/Washer Switch in the OFFposition, verify the scan tool Windshield Wiper Switch parameter is OFF.
• If not the specified value, refer to Windshield Wiper/Washer Switch Circuit Test.
3. S82 Windshield Wiper/Washer Switch in the OFF position, verify the scan tool Windshield Wiper High Speed Switch parameter is INACTIVE.
• If not the specified value, refer to Windshield Wiper/Washer Switch Circuit Test.
4. S82 Windshield Wiper/Washer Switch in the LOW position, verify the scan tool Windshield Wiper Switch parameter is LOW.
• If not the specified value, refer to Windshield Wiper/Washer Switch Circuit Test.
5. S82 Windshield Wiper/Washer Switch in the HIGH position, verify the scan tool Windshield Wiper High Speed Switch parameter is ACTIVE.
• If not the specified value, refer to Windshield Wiper/Washer Switch Circuit Test.
6. S82 Windshield Wiper/Washer Switch in the INT position, cycling the delay adjustment switch from long delay to short delay, observe the scan tool Windshield Wiper Switch parameter while cycling the delay adjustment switch from long delay to short delay. The parameter should cycle between Delay 1 through Delay 5 as each delay position is selected.
• If not the specified value, refer to Windshield Wiper/Washer Switch Circuit Test.
7. S82 Windshield Wiper/Washer Switch in the LOW position, verify the windshield wipers are cycling at the low speed.
• If the wipers are not operating at the low speed, refer to Windshield Wiper Motor Circuit Test.
8. S82 Windshield Wiper/Washer Switch in the HIGH position, verify the windshield wipers are cycling at the highspeed.
• If the wipers are not operating at the highspeed, refer to Windshield Wiper Motor Circuit Test.
9. S82 Windshield Wiper/Washer Switch in the INT position, cycling the delay adjustment switch from long delay to short delay. Verify the wiper delay time decreases from long delay to short delay as each delay position is selected.
• If the delay does not change as specified, refer to Windshield Wiper Motor Circuit Malfunction.
10. Observe the scan tool BCM Wiper Park Switch parameter. The reading should display Active when the wipers are parked and Inactive with the wipers ON or out of the park position.
• If the Wiper Park Switch parameter is always Active or Inactive, perform Wiper Park Circuit Test.
Circuit/System Testing
Windshield Wiper/Washer Switch Circuit Test
1. Ignition OFF, Retained Accessory Power OFF, disconnect the X1 harness connector at the S82 Windshield Wiper/Washer Switch.
2. Ignition OFF, test for less than 5 ohm between the ground circuit terminal 2 and ground.
• If greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the K9 BCM.
3. Ignition ON, test for B+ between the signal circuit terminal 3 and ground.
• If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
4. Test for B+ between the signal circuit terminal 5 and ground.
• If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
5. Test for B+ between the signal circuit terminal 1 and ground.
• If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
6. If all circuits test normal, test or replace the S82 Windshield Wiper/Washer Switch.
Windshield Wiper Motor Circuit Test
1. Ignition OFF, Retained Accessory Power OFF, disconnect X1 harness connector at M75 Windshield Wiper Motor.
2. Test for less than 5 ohm between the ground circuit terminal 2 and ground.
• If greater than the specified value, test the ground circuit for an open/high resistance.
3. Ignition ON, verify that a test lamp illuminates between B+circuit terminal 1 and ground.
• If the test lamp does not illuminate, test or replace the X50A underhood fuse block.
4. Ignition ON, test for 4-12 V between the communication signal circuit terminal 4 and ground.
• If not within the specified range, test the signal circuit for an open/high resistance or a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
5. If all circuits test normal, replace the M75 Windshield Wiper Motor.
Wiper Park Circuit Test
1. Ignition OFF, disconnect X1 harness connector at M75 Windshield Wiper Motor.
2. Ignition ON, test for 11-14 V between the park signal circuit terminal 3 and ground.
• If not within the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.
3. If all circuits test normal, replace the M75 Windshield Wiper Motor.
Component Testing
Multifunction Switch - Static Test
1. Disconnect the X1 harness connector at the S82 Windshield Wiper/Washer Switch.
2. With the S82 Windshield Wiper/Washer Switch in the HIGH position, test for less than 5 ohm between the terminal 2 and the signal terminal 1.
• If greater than the specified value, replace the S82 Windshield Wiper/Washer Switch.
3. While cycling the S82 Windshield Wiper/Washer Switch through each delay and speed position, test for the specified resistance between the low reference terminal 2 and the signal terminal 3.
Note: If the switch tests open in any switch position other than OFF, test the signal circuits for a short to voltage before replacing the switch.
If any switch position is not within the specified range, replace the S82 Windshield Wiper/Washer Switch.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Windshield Wiper Motor Replacement Service and Repair
* Windshield Wiper and Washer Switch Replacement Service and Repair
* Control Module References Control Module References for BCM replacement, setup, and programming