Circuit/System Testing

Windshield Wiper/Washer Switch

1. Ignition OFF, disconnect the harness connector at the windshield wiper/washer switch.
2. Ignition OFF, test for less than 20 ohms between the low reference circuit terminal B and ground.
   • If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit test normal, replace the BCM.
3. Ignition ON, verify the scan tool Windshield Washer Switch parameter is Inactive.
   • If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the BCM.
4. Install a 3A fused jumper wire between the signal circuit terminal A and ground. 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 windshield wiper/washer switch.

Washer Pump Circuit Malfunction.

1. Ignition OFF, disconnect the FRT/WSW relay.
2. Ignition ON, verify 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.
3. Verify a test lamp illuminates between the B+ circuit terminal 87 and ground.
   • If the test lamp does not illuminate, replace the underhood fuse block.
4. Verify a test lamp illuminates between the B+ circuit terminal 86 and ground.
   • If the test lamp does not illuminate, replace the underhood fuse block.
5. Disconnect the harness connector at the windshield washer fluid pump.
6. Test for less than 5 ohms between the ground circuit terminal B and ground.
   • If greater than the specified ranges, test the ground circuit for an open/high resistance.
7. Connect the harness connector at the windshield washer fluid pump.
8. Connect a 10A fused jumper wire between the B+ circuit terminal 87 and the control circuit terminal 30. Verify the windshield washer fluid pump is activated.
   • If the windshield washer fluid pump does not activate, test the control circuit for an open/high resistance. If the FRT/WSW fuse is open, test the control circuit for a short to ground. If the circuit tests normal, test or replace the windshield washer fluid pump.
9. Connect a test lamp between the B+ circuit terminal 86 and the control circuit terminal 85.
10. Command the windshield washer fluid pump ON and OFF with the 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 control circuit for a short to ground. If the circuit tests normal, replace the BCM.
    • If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
11. If all circuits test normal, test or replace the FRT/WSW relay.