Circuit/System Testing
Windshield Wiper Switch Malfunction
- Ignition OFF, disconnect the harness connector at the Windshield Wiper/Washer Switch.
- Test for less than 40 Ω between the low reference circuit terminal 8 and ground.
- If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit test normal, replace the BCM.
- Ignition ON, verify the scan tool Windshield Wiper Switch parameter is Off.
- If not the specified value, test the signal circuit terminal 7 for a short to ground. If the circuit tests normal, replace the BCM.
- Verify the scan tool Wiper High Speed Switch parameter is Inactive.
- If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the BCM.
- Install a 3A fused jumper wire between the signal circuit terminal 7 and ground. Verify the scan tool Windshield Wiper Switch parameter is Switch Fault.
- 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.
- Install a 3A fused jumper wire between the signal circuit terminal 4 and ground. Verify the scan tool Wiper High Speed 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.
- If all circuits test normal, test or replace the Windshield Wiper/Washer Switch.
Windshield Wiper Motor Malfunction
- Ignition OFF, disconnect WIPER LO relay.
- Ignition OFF, wait 20 seconds, Test for less than 1Ω between the ground circuit terminal 85 and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Ignition OFF, wait 20 seconds, test for less than 1Ω between the ground circuit terminal 87A 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 87 and ground.
- If the test lamp does not illuminate, replace the underhood fuse block.
- Ignition OFF, wait 20 seconds, connect a test lamp between the control circuit terminal 86 and the ground circuit terminal 85.
- Ignition ON, command the WIPER LO relay 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 BCM.
- 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 BCM.
- Ignition OFF, disconnect the WIPER HIGH relay.
- Test for less than 1 Ω between the control circuit terminal 30 at the WIPER LO relay and the control circuit terminal 30 at the WIPER HIGH relay.
- If greater than the specified range, replace the underhood fuse block.
- Connect the WIPER LO relay.
- Ignition OFF, wiper switch OFF, wait 20 seconds, Test for less than 1 Ω between the control circuit terminal 30 and ground.
- If greater than the specified range, test or replace the WIPER LO relay.
- Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 85 and ground.
- If the test lamp does not illuminate, replace the underhood fuse block.
- Ignition OFF, connect a test lamp between the control circuit terminal 30 and ground.
- Command the WIPER LO relay ON and OFF with a scan tool. The test lamp should turn illuminate.
- If the test lamp does not illuminate, replace the WIPER LO relay.
- Ignition OFF, remove WIPER HIGH relay, connect a test lamp between the B+ circuit terminal 85 and the control circuit terminal 86.
- Command the Wiper High 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 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.
- Ignition OFF, connect the WIPER HIGH relay. Disconnect the harness connector at the windshield wiper motor.
- Test for less than 5Ω between the ground circuit terminal 3 and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Connect a test lamp between the control circuit terminal 1 and ground.
- Ignition ON, command the WIPER LO relay 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, test or replace the WIPER HIGH relay.
- 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, test or replace the WIPER HIGH relay.
- Ignition OFF, connect a test lamp between the control circuit terminal 2 and ground.
- Lo wipers ON, command the Wiper High speed relay 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, test or replace the WIPER HIGH relay.
- 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, test or replace the WIPER HIGH relay.
- Wipers OFF, test for B+ between the signal circuit terminal 4 and ground.
- If not the specified value, test the signal circuit for a short to ground or an open high resistance. If the circuit tests normal, replace the BCM.
- If all circuits test normal, test or replace the windshield wiper motor.