Rear Washer System Malfunction
Rear Washer 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
When the Body Control Module (BCM) detects that the Rear Wiper/Wash switch has activated the momentary Wash switch, it activates a High Side Drive output which supplies battery to the coil of the rear washer pump relay. This energizes the relay, which switches battery power to the washer pump motor. The BCM will also activate continuous low speed windshield wipers as described above. This Washer and Wiper operation shall be continued so long as the switch remains active. Upon termination, the rear wash motor will be deactivated and the wiper shall move to its Park position and deactivate.
Reference Information
Schematic Reference
Wiper/Washer Schematics Electrical Diagrams
Connector End View Reference
Component Connector End Views Sunshade - Left
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 Programming and Relearning for scan tool information
Circuit/System Verification
Operate the rear washers by using the S82 Windshield Wiper/Washer Switch. Verify the G24 Windshield Washer Pump activates.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the S82 Windshield Wiper/Washer Switch.
2. Test for less than 5 ohms between terminal 2 at the S82 Windshield Wiper/Washer Switch harness connector and ground.
• If not the specified value, test the low reference circuit for an open/high resistance and a short to voltage.
3. Ignition OFF, disconnect the harness connector X7 at the K9 Body Control Module.
4. Test for 150-200 ohms between the harness connector X7 terminal 8 at the K9 Body Control Module and ground.
• If the resistance is not within the specified range, test the control circuit for a short to voltage, short to ground or an open/high resistance.
5. If all circuits test normal, test or replace the K9 Body Control Module.
6. Disconnect the harness connector at the G24 Windshield Washer Pump. Verify there is no wash function activated.
7. Test for less than 5 ohms between the G24 Windshield Washer Pump harness connector terminals 1 and ground.
• If not the specified value, test the ground circuit for an open/high resistance and a short to voltage.
8. Test for less than 5 ohms between the G24 Windshield Washer Pump harness connector terminals 2 and ground.
• If not the specified value, test the ground circuit for an open/high resistance and a short to voltage.
9. If all circuits test normal, test or replace the X50A Fuse Block - Underhood.
Component Testing
Output Control Tests
Ignition ON, command the Rear Washer ON and OFF with the rear washer switch. Observe the KR6 Rear Window Washer Pump Relay clicks and the G24 Windshield Washer Pump runs.
If the KR6 Rear Window Washer Pump Relay does not work, replace the X50A Fuse Block - Underhood.
If the KR6 Rear Window Washer Pump Relay does work, but the G24 Windshield Washer Pump does not run, test the G24 Windshield Washer Pump ground and control circuit.
If all circuits test normal, replace the G24 Windshield Washer Pump.
Multifunction Switch
Static Test
1. Ignition OFF, remove the S82 Windshield Wiper/Washer Switch.
2. Test for 5.90-6.40 kohms between signal terminal 2 and 4 at the S82 Windshield Wiper/Washer Switch while activating the rear wash switch.
• If the resistance is not within the specified range, replace the S82 Windshield Wiper/Washer Switch.
Washer Pump
Dynamic Test
1. Ignition OFF, disconnect the harness connector at the G24 Windshield Washer Pump.
2. Install a 10 A fused jumper wire between the control terminal 2 and 12 V. Install a jumper wire between the ground terminal 1 and ground.
3. Verify the G24 Windshield Washer Pump is activated.
• If the G24 Windshield Washer Pump does not activate , replace the G24 Windshield Washer Pump.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Control Module References Programming and Relearning for BCM replacement, programming and setup
* Relay Replacement (Within an Electrical Center) Relay Replacement (Within an Electrical Center)Relay Replacement (Attached to Wire Harness) Relay Replacement (Attached to Wire Harness)
* Windshield Washer Pump Replacement Windshield Washer Pump Replacement
* Windshield Wiper and Washer Switch Replacement Service and Repair