PRE-RELEASE
Washer Malfunction
| Washer Malfunction |
| Diagnostic Instructions |
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Perform the
Diagnostic System Check - Vehicle
prior to using this diagnostic procedure.
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Review
Strategy Based Diagnosis
for an overview of the diagnostic approach.
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Diagnostic Procedure Instructions
provides an overview of each diagnostic category.
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| Diagnostic Fault Information |
| Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
| Rear Washer Switch Control | 5 | 4 | 4 | - |
| Rear Washer Relay Control | B3811 02 | 4 | 5 | - |
| Rear Washer Fluid Pump Control | 4 | 4 | 5 | - |
| Rear Washer Fluid Pump Ground | - | 4 | 4, 5 | - |
| Windshield Washer Switch Signal | 2 | 1 | 1 | - |
| Washer Fluid Level Switch Signal | 3 | 3 | 3 | - |
| Windshield Washer Fluid Pump Control | 1 | 1 | 2 | - |
| Windshield Washer Relay Control | B3873 02 | 1 | 2 | - |
| Windshield Washer Fluid Pump Ground | - | 1 | - | - |
| Washer Fluid Level Switch Ground | 3 | 3 | 3 | - |
| 1. Front Washer Inoperative 2. Front Washer Always ON 3. Washer Fluid Level Inoperative 4. Rear Washer Inoperative 5. Rear Washer Always ON | ||||
| Circuit/System Description |
The body control module (BCM) controls the windshield washer fluid pump based on an input from the wiper/washer switch. The (BCM) monitors the washer switch through the windshield washer switch signal circuit. When the wash switch is closed, ground is supplied to the windshield washer switch signal circuit. When this is the case, the BCM will command the windshield 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 wipes 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.
| Reference Information |
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
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Circuit Testing
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Connector Repairs
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Testing for Intermittent Conditions and Poor Connections
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Wiring Repairs
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Scan Tool Reference
Control Module References for scan tool information
| Circuit/System Verification |
| 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.
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| 2. |
If the reading does not change between INACTIVE and ACTIVE, refer to Windshield Washer Switch Circuit Test.
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| 3. |
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.
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| 4. |
If windhield washers do not turn ON and OFF, refer to the Washer Pump Circuit Test.
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| 5. |
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.
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| 6. |
If the rear washer does not turn ON and OFF, refer to the Washer Pump Circuit Test.
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| 7. |
If the rear washer turns ON and OFF, refer to Rear Washer Switch Circuit Test.
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| 8. |
Command the Headlamp Washer Relay Command ON and OFF with a scan tool. The headlamp washers should turn ON and OFF when changing between the commanded states.
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| 9. |
If the headlamp washers do not turn ON and OFF, refer to
Headlamp Washer Malfunction
.
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| 10. |
Verify the windshield washer fluid level is above the minimum level.
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| 11. |
If not above the minimum level, fill the reservoir and inspect for leaks. If the low washer fluid indicator is still ON, refer to Low Washer Fluid Indicator Test.
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| Circuit/System Testing |
Windshield Washer Switch Circuit Test
| 1. |
Ignition OFF, disconnect the X1 harness connector at the S82 windshield wiper/washer switch.
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| 2. |
Verify that a test lamp illuminates between the low reference terminal 2 and B+.
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| 3. |
If the test lamp does not illuminate, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K9 BCM.
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| 4. |
Ignition ON, verify the scan tool Windshield Washer Switch parameter is INACTIVE.
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| 5. |
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.
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| 6. |
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.
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| 7. |
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.
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| 8. |
If all circuits test normal, test or replace the S82 windshield wiper/washer switch.
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Rear Washer Switch Circuit Test
| 1. |
Ignition OFF, disconnect the X1 harness connector at the S82 windshield wiper/washer switch.
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| 2. |
Verify that a test lamp illuminates between the low reference terminal 2 and B+.
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| 3. |
If the test lamp does not illuminate, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K9 BCM.
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| 4. |
Ignition ON, verify the rear washer is OFF.
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| 5. |
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.
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| 6. |
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.
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| 7. |
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.
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| 8. |
If all circuits test normal, test or replace the S82 windshield wiper/washer switch.
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Washer Pump Circuit Test
| 1. |
Ignition OFF, disconnect the X2 harness connector at the X50A underhood fuse block.
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| 2. |
Connect a test lamp between the control circuit terminal 14 and ground.
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| 3. |
Ignition ON, command the Winshield Washer Relay Command ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
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| 4. |
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.
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| 5. |
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.
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| 6. |
Connect a test lamp between the control circuit terminal 10 and ground.
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| 7. |
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.
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| 8. |
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.
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| 9. |
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.
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| 10. |
Ignition OFF, connect the X2 harness connector at the X50A underhood fuse block and disconnect the harness connector at the G24 windshield washer pump.
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| 11. |
Connect a test lamp between control circuit terminal 2 and ground.
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| 12. |
Ignition ON, command the Windshield Washer Relay Command ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
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| 13. |
If the test lamp is always ON, test the control circuit for a short to voltage. If the cirucit tests normal, replace the X50A underhood fuse block.
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| 14. |
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 underhood fuse block.
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| 15. |
Connect a test lamp between control circuit terminal 1 and ground.
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| 16. |
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.
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| 17. |
If the test lamp is always ON, test the control circuit for a short to voltage. If the cirucit tests normal, replace the X50A underhood fuse block.
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| 18. |
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 underhood fuse block.
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| 19. |
If all circuits test normal, test or replace the G24 windshield washer pump.
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Low Washer Fluid Indicator Test
| 1. |
Verify the washer fluid reservoir is filled up.
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| 2. |
Ignition OFF, disconnect the harness connector at the B118B windshield washer fluid level switch.
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| 3. |
Test for less than 5 Ω between the ground terminal 1 and ground.
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| 4. |
If greater than the specified range, test the ground circuit for an open/high resistance.
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| 5. |
Ignition OFF, disconnect the X1 harness connector at the P16 instrument cluster.
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| 6. |
Test for less than 5 Ω between the signal circuit terminal 2 at the B118B Windshield Washer Fluid Level Switch harness connector and signal terminal 15 at the P16 instrument cluster harness connector.
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| 7. |
If greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance.
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| 8. |
Reconnect all harness connectors.
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| 9. |
Ignition ON, command the Driver Information Center Segment test ON and OFF with the scan tool, verify that the low washer fluid indicator display reacts to ON and OFF positions.
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| 10. |
If the low washer fluid indicator display is always ON or always OFF, replace the P16 instrument cluster.
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| 11. |
If the low washer fluid indicator display changes between ON and OFF, test or replace the B118B windshield washer fluid level switch.
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| Component Testing |
Washer Switch Test
| 1. |
Disconnect the X1 harness connector at the S82 windshield wiper/washer switch.
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| 2. |
Test for less that 5 Ω between signal circuit terminal 5 and ground.
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| 3. |
If not the specified range, replace the S82 windshield wiper/washer switch.
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| 4. |
Test for less that 5 Ω between signal circuit terminal 4 and ground.
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| 5. |
If not the specified range, replace the S82 windshield wiper/washer switch.
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Washer Pump Test
| 1. |
Ignition OFF, disconnect the harness connector at the G24 windshield washer pump.
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| 2. |
Install a 10 A fused jumper wire between the control terminal 2 and 12 V. Install a jumper wire between the ground terminal 1 and ground.
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| 3. |
Verify the G24 windshield washer pump is activated.
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| 4. |
If the G24 windshield washer pump does not activate, replace the G24 windshield washer pump.
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Low Washer Fluid Indicator Test
| 1. |
Ignition OFF, remove the B118B windshield washer fluid level switch.
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| 2. |
Install a wire at terminal 1 and terminal 2. Observe the resistance while moving the level switch.
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| 3. |
The resistance should be changing between less than 5 Ω infinite resistance while moving the level switch.
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| 4. |
If not the specified range, replace the B118B windshield washer fluid level switch.
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| Repair Instructions |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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Windshield Wiper and Washer Switch Replacement
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Control Module References
for BCM replacement, setup, and programming
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