The windshield washer function is controlled by the body control module (BCM). When the washer switch is pressed, ground is applied through the switch contacts and the signal circuit to the BCM indicating the wash request. The BCM then applies ground through the control circuit to the coil side of the FRT WASH relay energizing the relay. With the relay energized, battery voltage is applied through the switch contacts of the relay, the FRT WASH fuse and the control circuit to the windshield washer fluid pump.

Schematic Reference

Wiper/Washer Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

Scan Tool Reference

Control Module References

1. Ignition ON, observe the scan tool Windshield Washer Switch parameter while pressing and releasing the washer switch. The reading should change between Active and Inactive.

⇒	If the reading does not change between the specified values, refer to the Windshield Washer Switch Circuit Test.

2. Connect a test lamp between the relay side of the FRT WASH fuse and ground.
3. Ignition ON, verify that the test lamp turns ON and OFF while pressing and releasing the windshield washer switch.

⇒	If the test lamp does not turn ON and OFF while changing between the commanded states, refer to the Windshield Washer Pump Relay Control Circuit Test.

4. If the washer pump does not operate, refer to the Windshield Washer Pump Circuit Test.

Windshield Washer Switch Circuit Test

1. Ignition OFF, disconnect the X3 harness connector at the turn signal multifunction switch.
2. Test for less than 20 ohms between the low reference circuit terminal M and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance.

3. Verify the scan tool Windshield Wiper Switch parameter is Off.

⇒	If not Off, test the signal circuit terminal E for a short to voltage. If the circuit tests normal, replace the body control module.

4. Install a 3A fused jumper wire between the signal circuit terminal L and the low reference circuit terminal M. Verify the scan tool Windshield Washer Switch parameter is Active.

⇒	If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the turn signal multifunction switch.

Windshield Washer Pump Relay Control Circuit Test

1. Ignition OFF, disconnect the X4 harness connector at the BCM.
2. Ignition ON, verify the windshield washer pump is not on.

⇒	If the windshield washer pump is on, test the windshield washer pump relay control circuit terminal 15 for a short to ground. If the circuit tests normal replace the underhood fuse block.

3. Install a 10A fused jumper wire between the relay control circuit terminal 15 and ground. Verify the windshield washer pump is on.

⇒	If the windshield washer pump is not on, test the relay control circuit for a short to voltage or an open/high resistance. If the circuit tests normal replace the underhood fuse block.

4. If all circuits test normal, replace the BCM.

Windshield Washer Pump Circuit Test

1. Ignition OFF, disconnect the harness connector at the windshield washer pump.
2. Test for less than 1.0 ohm between the ground circuit terminal B and ground.

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

3. Connect a test lamp between the control circuit terminal A and the ground circuit terminal B.
4. Command the Wiper Washer Motor ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

⇒	If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the underhood fuse block.

⇒	If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the underhood fuse block.

5. If all circuits test normal, test or replace the windshield washer pump.

Turn Signal Multifunction Switch

1. Ignition OFF, disconnect the X1 harness connector at the turn signal multifunction switch.
2. With the wiper switch in the HIGH position, test for less than 2 ohms between the low reference terminal M and the signal terminal K.

⇒	If greater than the specified range, replace the windshield wiper washer switch.

Important: 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.

3. While cycling the wiper switch through each delay and speed position, test for the specified resistance between the low reference terminal M and the signal terminal N.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.