Diagnostic Instructions
Circuit/System Description
The windshield washer solvent heater operates along side the standard windshield wiper washer system. When a heated washer cycle is activated, the solvent heater controls the windshield washers through the windshield washer switch signal circuit. The windshield
heated washer fluid module is supplied with high current power and ground circuits that are used to energize the heater coils. The low current logic voltage is supplied to the module through the BCM. The heated washer cycle operation is activated by a separate
switch located on the headlamp switch. When the heated washer fluid switch is pressed, the heated wash switch signal circuit is momentarily grounded and the heated washer cycle is activated. During the heated wash cycle the 3 heater elements in the solvent heater
are energized, and when the solvent temperature reaches approximately 70° C (160° F) the heater grounds the washer switch signal circuit until the heated solvent is dispensed. The heated washer cycle will run 4 heat and wash actions unless
deactivated by the heated washer switch.
Reference Information
Schematic Reference
Wiper/Washer Schematics
Connector End View Reference
Wiper/Washer Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
- Ignition ON, verify the washers operate using the washer switch.
- Depress the heated washer switch. The heater washer fluid system should begin to cycle and the DIC should displays the heated washer fluid pending message.
⇒ | If the heated washer fluid system does not begin to cycle, refer to Windshield Washer Solvent Heater Malfunction. |
⇒ | If the DIC does not display the heated washer fluid pending message, refer to Heated Washer Fluid Indicator Malfunction. |
Circuit/System Testing
Windshield Washer Solvent Heater Malfunction
- Ignition OFF, disconnect the X1 harness connector at the windshield heated washer fluid module.
- Test for less than 5 ohms of resistance between the ground circuit terminal 2 and ground.
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground.
⇒ | If the test lamp does not illuminate, test the battery positive voltage circuit for an open/high resistance. If the circuit fuse is open, test the B+ circuit for a short to ground. If the circuit test normal, replace the windshield heated
washer fluid module. |
- Ignition OFF, connect the X1 harness connector at the windshield heated washer fluid module. Disconnect the X2 harness connector at the windshield heated washer fluid module.
- Test for less than 5 ohms of resistance between the ground circuit terminal 4 and ground.
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 6 and ground.
⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, refer to
Power Mode Mismatch
. |
- Verify the scan tool Windshield Washer Switch parameter displays Inactive.
- Install a 3A fused jumper wire between the signal circuit terminal 5 and ground. Verify the scan tool Windshield Washer Switch parameter displays 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, refer to
Windshield Wiper System Malfunction
. |
- Ignition OFF, connect a test lamp between the signal circuit terminal 1 and B+.
- Command the heated washer system ON and OFF using the header 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 ground. If the circuit tests normal, test or replace the headlamp switch. |
⇒ | If the test lamp is always OFF, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, test or replace the headlamp switch. |
- If all circuits test normal, test or replace the windshield heated washer fluid module.
Heated Washer Fluid Indicator Malfunction
- Ignition OFF, disconnect the X2 harness connector at the windshield heated washer fluid module.
- Verify the heated washer fluid pending message is not displayed on the DIC.
⇒ | If the message is displayed, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the IPC. |
- Ignition ON, install a 3A fused jumper wire between the signal circuit terminal 2 and ground. Verify the heated washer fluid pending message is displayed on the DIC.
⇒ | If the message is not displayed, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC. |
- If all circuits test normal, test or replace the windshield heated washer fluid module.
Component Testing
Heated Washer Fluid Switch
- Ignition OFF, disconnect the harness connector at the headlamp switch.
- Test for infinite resistance between the signal terminal 10 and the ground terminal 8 with the switch in the open position.
⇒ | If not the specified value, replace the headlamp switch. |
- Test for less than 3 ohms of resistance between the signal terminal 10 and the ground terminal 8 with the switch in the closed position.
⇒ | If greater than the specified range, replace the headlamp switch. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.