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Washer Malfunction



Washer Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview)provides an overview of each diagnostic category



Diagnostic Fault Information






Circuit/System Description

The rear washer is activated based on an input from the rear washer switch. When the rear washer switch is pressed, B+ is applied through the rear window wiper switch signal circuit to the rear window wiper motor indicating the rear window washer operation request. The logic within the rear wiper motor interprets this request, then applies B+ through the rear window washer pump control circuit to the coil side of the REAR WASH relay, energizing the relay. Battery voltage from the REAR WASH fuse is then applied through the switch side of the relay to the washer pump.


Reference Information
Schematic Reference

Wiper/Washer Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Wiper/Washer System Description and Operation (Wiper/Washer System Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning)for Scan Tool Information


Circuit/System Verification

1. Ignition ON and the liftgate closed, verify that the driver information center (DIC) LIFT GATE AJAR message is not illuminated.

• If the LIFT GATE AJAR message is illuminated, refer to Liftgate Ajar Indicator Malfunction (Liftgate Ajar Indicator Malfunction) .

2. Ignition ON, verify the rear wiper operates normally using the rear wiper switch.

• If the rear wipers do not operate properly, refer to Windshield Wiper System Malfunction (Windshield Wiper System Malfunction) .

3. Operate the rear washers using the rear washer switch. The rear washer pump should activate.



Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the rear window wiper motor.
2. Install a test lamp between the signal circuit terminal C and ground.
3. Ignition ON, command the rear washers ON and OFF using the rear washer switch. The test lamp should turn ON and OFF when changing between the commanded states.

• If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, test or replace the rear wiper/washer switch.
• If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the rear wiper/washer switch.

4. Ignition OFF, connect the harness connector at the rear window wiper motor. Disconnect the REAR WASH relay.
5. Ignition ON, verify a test lamp does not illuminate between the control circuit terminal R18 and ground.

• If the test lamp illuminates, test the control circuit for a short to voltage.

6. Ignition OFF, test for less than 5 ohms of resistance between the ground circuit terminal R20 and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

7. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal R19 and ground.

• If the test lamp does not illuminate, test the REAR WASH fuse for an open.

8. Install a test lamp between the control circuit terminal R17 and ground.
9. Command the rear washers ON and OFF using the rear washer switch. The test lamp should turn ON and OFF when changing between the commanded states.

• If the test lamp is always ON, test the relay control circuit for an short to voltage. If the circuit tests normal, replace the rear window wiper motor.
• If the test lamp is always OFF, test the relay control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the rear window wiper motor.

10. Ignition OFF, disconnect the harness connector at the rear window washer fluid pump.
11. Test for less than 20 ohms of resistance between the ground circuit terminal A and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

12. Connect a 3A fused jumper wire between the B+ circuit terminal R19 and the control circuit terminal R18.
13. Verify that a test lamp illuminates between the control circuit terminal B and ground.

• If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the REAR WASH relay.

14. If all circuits test normal, test or replace the rear window washer fluid pump.



Component Testing


Rear Window Wiper/Washer Switch
1. Ignition OFF, disconnect the harness connector at the rear wiper/washer switch.
2. With the rear washer switch open, test for infinite resistance between the B+ terminal 5 and the signal terminal 3.

• If not the specified value, replace the rear wiper/washer switch.

3. With the rear washer switch closed, test for less than 2 ohms of resistance between the B+ terminal 5 and the signal terminal 3.

• If greater than the specified range, replace the rear wiper/washer switch.




Rear Window Washer Fluid Pump
1. Ignition OFF, disconnect the harness connector at the rear window washer fluid pump.
2. Install a 20A fused jumper wire between the control terminal B and 12 volts. Install a jumper wire between the ground terminal A and ground.
3. Verify the rear window washer fluid pump is activated.

• If the washer fluid pump does not activate, replace the rear window washer fluid pump.




Relay Test
1. Ignition OFF, disconnect the relay.
2. Test for 70-100 ohms of resistance between terminals 85 and 86.

• If the resistance is not within the specified range, replace the relay.

3. Test for infinite resistance between the following terminals:

* 30 and 85
* 30 and 86
* 30 and 87
* 85 and 87


• If not the specified value, replace the relay.

4. Install a 10A fused jumper wire between relay terminal 85 and B+. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms of resistance between terminals 30 and 87.

• If greater than the specified range, replace the relay.




Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Rear Window Washer Pump Replacement (Rear Window Washer Pump Replacement)
* Rear Window Wiper and Washer Switch Replacement (Service and Repair)
* Liftgate Wiper Motor Replacement (Liftgate Wiper Motor Replacement)
* Relay Replacement (Attached to Wire Harness) (Relay Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (Relay Replacement (Within an Electrical Center))


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