When the washer switch is pressed, the windshield wiper switch sends a voltage signal through windshield washer switch signal circuit to the wiper motor module and the instrument panel module (IPM) indicating the wash command. Every fourth time the windshield washer system is commanded ON, the IPM will initiate a headlamp wash cycle by pulling the headlamp washer relay control circuit low energizing the relay. The relay then closes its switch contacts applying battery positive voltage through the headlamp washer pump motor control circuit to the headlamp washer pump motor. The pump motor then runs spraying washer fluid on the headlamps. A headlamp wash cycle consists of a prewash, then a pause, and then a wash operation.

Schematic Reference

Wiper/Washer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Wiper/Washer System Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for Scan Tool Information

1. Verify the windshield washers operate normally.
2. Verify the headlamps operate normally.
3. Verify the windshield washer fluid level is above the minimum level.

⇒	If not above the minimum level, fill the reservoir and inspect for leaks.

4. Verify the scan tool IPC Washer Fluid Level parameter is OK.

1. Ignition OFF, disconnect the HEADLAMP WASH Relay.
2. Ignition ON, verify that a test lamp illuminates between the accessory voltage terminal 85 and ground.

⇒	If the test lamp does not illuminate test the control circuit for an open/high resistance.

3. Verify that a test lamp does not illuminate between the control circuit terminal 30 and ground.

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

4. Connect a test lamp between the control circuit terminal 87 and the ground circuit terminal 86.
5. Command the Headlamp Washer Relay On and OFF with a scan tool. The test lamp should turn ON and OFF when changing between 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 Instrument Panel Module (IPM).

⇒	⇒ If the test lamp is always OFF, test the control circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the Instrument Panel Module (IPM).

6. Ignition OFF, disconnect the harness connector at the headlamp washer fluid pump.
7. Test for less than 5 ohm between the ground circuit terminal A and ground

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

8. Connect the harness connector at the headlamp washer fluid pump.
9. Install a 3A fused jumper wire between the B+ circuit terminal 87 and the control circuit terminal 30. Verify the headlamp washer fluid pump is activated.

⇒	If it does not activate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the headlamp washer fluid pump.

10. If all circuits test normal, test or replace the headlamp washer relay.

Headlamp Washer Fluid Pump Test

1. Ignition OFF, disconnect the harness connector at the windshield washer fluid pump.
2. Install a 20A fused jumper wire between the control terminal B and B+. Install a jumper wire between the ground terminal A and ground.
3. Verify the headlamp washer fluid pump is activated.

⇒	If the headlamp washer fluid pump does not activate, replace the washer fluid pump.

RelayTest

1. Ignition OFF, disconnect the relay.
2. Test for 60-200 ohms 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 86

•

30 and 87

•

30 and 85

•

85 and 87

⇒	If not the specified value, replace the relay.

Multifunction Switch

1. Ignition OFF, disconnect the harness connectors at the windshield wiper switch.
2. Test the resistance between terminals N and K. Rotate the wiper switch and compare the resistance readings to the values in the Windshield Wiper Switch Values table below for MIST, each DELAY and LOW speed.

⇒	If the resistance is not within the specified range, replace the turn signal/multifunction switch.

Important: If the switch tests open in any switch position other than Off, test the wiper/washer switch signal circuits for a short to voltage before replacing the switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.