Orlando

Washer Malfunction

The body control module (BCM) controls the windscreen washer fluid pump based on an input from the wiper/washer switch. The BCM monitors the washer switch through the windscreen washer switch signal circuit. When the wash switch is closed, ground is supplied to the windscreen washer switch signal circuit. When this is the case, the BCM will command the windscreen washer fluid pump and the low speed wipers on.

On some vehicles warning information (wash fluid low and heated wash ON/OFF) will be conveyed via the GMLAN to the controls and displays subsystem (responsible for display). This subsystem will provide visual feedback to the customer while in the RUN power mode.

When the BCM detects that the rear wiper/wash switch has activated the momentary wash switch, it activates a high side drive output which supplies battery to the coil of the rear washer pump relay. This energizes the relay, which switches battery power to the washer pump motor. The BCM will also activate continuous low speed windshield wipers as described above. This washer and wiper operation shall be continued so long as the switch remains active. Upon termination the rear wash motor will be deactivated and the wiper shall move to its park position and deactivate.

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

⇒	If the reading does not change between INACTIVE and ACTIVE, refer to Windshield Washer Switch Circuit Test.

2. Command the Windshield Washer Relay Command ON and OFF with a scan tool. The windshield washers should turn ON and OFF when changing between the commanded states.

⇒	If windshield washers do not turn ON and OFF, refer to the Washer Pump Circuit Test.

3. Command the Rear Washer Relay Command ON and OFF with a scan tool. The rear washer should turn ON and OFF when changing between the commanded states.

⇒	If the rear washer does not turn ON and OFF, refer to the Washer Pump Circuit Test.

⇒	If the rear washer turns ON and OFF, refer to Rear Washer Switch Circuit Test.

Windshield Washer Switch Circuit Test

1. Ignition OFF, disconnect the X1 harness connector at the S82 windshield wiper/washer switch.
2. Test for less than 5 Ω between the low reference terminal 2 and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K9 BCM.

3. Ignition ON, verify the scan tool Windshield Washer Switch parameter is INACTIVE.

⇒	If not the specified value, test the signal circuit terminal 5 for a short to ground. If the circuit tests normal, replace the K9 BCM.

4. Install a 3 A fused jumper wire between the signal circuit terminal 5 and the ground circuit terminal 2. 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 K9 BCM.

5. If all circuits test normal, test or replace the S82 windscreen wiper/washer switch.

Rear Washer Switch Circuit Test

1. Ignition OFF, disconnect the X1 harness connector at the S82 windshield wiper/washer switch.
2. Test for less than 5 Ω between the low reference terminal 2 and ground

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K9 BCM.

3. Ignition ON, verify the rear washer is OFF.

⇒	If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the K9 BCM.

4. Install a 3 A fused jumper wire between the signal circuit terminal 4 and the ground circuit terminal 2. Verify the rear washer turns ON.

⇒	If the rear washer does not turn on, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 BCM.

5. If all circuits test normal, test or replace the S82 windscreen wiper/washer switch.

Washer Pump Circuit Test

1. Ignition OFF, disconnect the X2 harness connector at the X50A underbonnet fuse block.
2. Connect a test lamp between the control circuit terminal 60 and ground.
3. Ignition ON, command the Windscreen Washer Relay Command 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 K9 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 K9 BCM.

4. Connect a test lamp between the control circuit terminal 11 and ground.
5. Command the Rear Washer Relay Command 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 K9 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 K9 BCM.

6. Ignition OFF, connect the X2 harness connector at the X50A underhood fuse block and disconnect the harness connector at the G24 windshield washer pump.
7. Connect a test lamp between control circuit terminal 1 and ground.
8. Ignition ON, command the Windscreen Washer Relay Command 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 X50A underbonnet 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 X50A underbonnet fuse block.

9. Connect a test lamp between control circuit terminal 2 and ground.
10. Command the Rear Washer Relay Command 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 X50A underbonnet 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 X50A underbonnet fuse block.

11. If all circuits test normal, test or replace the G24 windscreen washer pump.

Washer Switch Test

1. Disconnect the X1 harness connector at the S82 windshield wiper/washer switch.
2. Test for less that 5 Ω between signal circuit terminal 5 and ground.

⇒	If not the specified range, replace the S82 windshield wiper/washer switch.

3. Test for less that 5 Ω between signal circuit terminal 4 and ground.

⇒	If not the specified range, replace the S82 windshield wiper/washer switch.

Washer Pump Test

1. Ignition OFF, disconnect the harness connector at the G24 windscreen washer pump.
2. Install a 10 A fused jumper wire between the control terminal 1 and B+. Install a jumper wire between the control terminal 2 and ground.
3. Verify the G24 windscreen washer pump is activated.

⇒	If the G24 windscreen washer pump does not activate, replace the G24 windscreen washer pump.

Perform the Diagnostic Repair Verification after completing the repair.