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Power Windows Malfunction



Power Windows Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information






Circuit/System Description

The driver and passenger door lock and side window switches are integrated control module switch assemblies. When a power window switch is activated in the up or down positions the driver door module (DDM) supplies power and ground to the window motor control circuits to drive the window motor in the required direction. Prior to activating a power window motor the DDM will supply the control circuit with a low current bias voltage in order to determine that a short to ground condition does not exist and during window motor operation the DDM continues to monitor the motor current to verify proper window motor operation.

Circuit/System Verification

1. Ignition ON, command driver power window UP and DOWN using the driver door switch, observe the operation of the driver window.

^ If the driver window is inoperative, refer to Driver Window Malfunction.

2. Command the front passenger power window UP and DOWN using the passenger door switch, observe the operation of the passenger window.

^ If the front passenger window is inoperative, refer to Passenger Window Malfunction.

3. Command the rear passenger power windows UP and DOWN with a scan tool, observe the operation of rear passenger power windows.

^ If either rear passenger power window is inoperative, refer to Rear Passenger Window Malfunction.

4. Observe the scan tool Driver Window RF Switch, Driver Window LR Switch and Driver Window RR Switch parameters while using the driver master control switches. The reading should change between OFF/UP/DOWN/EXPRESS DOWN.

^ If the parameter does not change, replace the DDM.

5. Observe the scan tool Window Lockout parameter while pressing and depressing the window lockout switch on the driver master control. The reading should change between ON and OFF.

^ If the parameter does not change, replace the DDM.

Circuit/System Testing

Driver Window Malfunction

1. Ignition OFF, disconnect the X1 harness connector at the DDM.
2. Test for less than 1.0 ohm between the ground circuit terminal A and ground.

^ If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal D and ground.

^ If the test lamp does not illuminate, test the B+ circuit for a short to ground or open/high resistance.

4. Ignition OFF, reconnect the harness connector at the DDM.
5. Ignition ON, observe the scan tool Driver Window Switch parameters while using the driver power window switch. The reading should change between OFF/UP/DOWN/EXPRESS DOWN.

^ If the parameter does not change, replace the DDM.

6. Ignition OFF, disconnect the harness connector at the driver window motor.
7. Connect a test lamp between control circuit terminal A and control circuit terminal B.
8. Ignition ON, command the driver window UP and DOWN by using the driver window switch. The test lamp should turn ON when commanding the UP and DOWN states.

^ If the test lamp is always OFF during either of the commands, test for a short to ground or open/high resistance on either control circuit. If the circuits test normal, replace the DDM.

^ If the test lamp is always ON, test for a short to voltage on either control circuit. If the circuits test normal, replace the DDM.

9. If all circuits test normal, test or replace the driver window motor.

Passenger Window Malfunction

1. Ignition OFF, disconnect the X1 harness connector at the FPDM.
2. Test for less than 1.0 ohm between the ground circuit terminal A and ground.

^ If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal D and ground.

^ If the test lamp does not illuminate, test the B+ circuit for a short to ground or open/high resistance.

4. Ignition OFF, reconnect the harness connector at the FPDM.
5. Ignition ON, observe the scan tool Psgr RF Window Switch parameters while using the passenger power window switch. The reading should change between OFF/UP/DOWN/EXPRESS DOWN.

^ If the parameter does not change, replace the FPDM.

6. Ignition OFF, disconnect the harness connector at the passenger window motor.
7. Connect a test lamp between control circuit terminal A and control circuit terminal B.
8. Ignition ON, command the passenger window UP and DOWN by using the passenger window switch. The test lamp should turn ON when commanding the UP and DOWN states.

^ If the test lamp is always OFF during either of the commands, test for a short to ground or open/high resistance on either control circuit. If the circuits test normal, replace the FPDM.

^ If the test lamp is always ON, test for a short to voltage on either control circuit. If the circuits test normal, replace the FPDM.

9. If all circuits test normal, test or replace the passenger window motor.

Rear Passenger Window Malfunction

1. Ignition OFF, disconnect the harness connector at the appropriate rear window switch.
2. Test for less than 1.0 ohm between the ground circuit terminal E and ground.

^ If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal A and ground.

^ If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

4. Test for more than 10 volts between the power window lockout rear control circuit terminal D and ground with the rear windows enabled on the driver master control.

^ If less than the specified range, test the control circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the BCM

5. Connect a test lamp between the power window switch rear down signal circuit terminal B and B+.
6. Command the appropriate rear window DOWN with a scan tool. The test lamp should turn ON when commanding the DOWN state.

^ If the test lamp is always OFF, test the signal circuit for a short to voltage or open/high resistance. If the circuits test normal, replace the BCM.

7. Connect a test lamp between the power window switch rear up signal circuit terminal C and B+.
8. Command the appropriate rear window UP with a scan tool, the test lamp should turn ON when commanding the UP state.

^ If the test lamp is always OFF, test the signal circuit for a short to voltage or open/high resistance. If the circuits test normal, replace the BCM.

9. Ignition OFF, reconnect the appropriate rear window switch and disconnect the harness connector at the appropriate rear window motor.
10. Connect a test lamp between control circuit terminal A and control circuit terminal B.
11. Ignition ON, command the appropriate rear window UP and DOWN by using the appropriate rear window switch. The test lamp should turn ON when commanding the UP and DOWN states.

^ If the test lamp is always OFF during either of the commands, test either control circuit for a short to ground or open/high resistance. If the circuits test normal, replace the appropriate rear window switch.

^ If the test lamp is always ON, test either control circuit for a short to voltage. If the circuits test normal, replace the appropriate rear window switch.

12. If all circuits test normal, test or replace the appropriate rear window motor.

Component Testing

1. Install a 25-amp fused jumper wire between the control terminal A and 12 volts. Momentarily install a jumper wire between the control terminal B and ground. The appropriate window motor should perform the UP or DOWN function.

^ If the function does not perform as specified, replace the appropriate window motor.

2. Reverse the jumper wires; the appropriate window motor should perform the DOWN or UP function.

^ If the function does not perform as specified, replace the appropriate window motor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Rear Side Door Window Switch Replacement
* Door Window Regulator Motor Replacement
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