GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

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

Circuit/System Description

When the ignition switch is in the RUN or ACCY position, or retained accessory power (RAP) is enabled and the driver or front passenger window switch is pressed in the down position, voltage is applied to the appropriate window motor causing that window to open. When the driver or front passenger window switch is pressed in the up position, voltage is applied to the appropriate window motor in the opposite direction causing that window to close.

Reference Information

Schematic Reference

Moveable Window Schematics

Connector End View Reference

Window Systems Connector End Views

Description and Operation

Power Windows Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Circuit/System Verification

Ignition ON, command the appropriate door window UP and DOWN by pressing the appropriate window switch. Observe the operation of the appropriate door window.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the driver window switch.
  2. Ignition OFF, test for less than 1 ohm of resistance between the ground circuit terminal F and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal C and ground.
  5. If the test lamp does not illuminate, test the B+ circuit for an open/high resistance. If the PWR WNDW circuit breaker is open, test the circuit terminal C for a short to ground.
    If all circuits test normal, test or replace the driver window switch.
  6. Ignition OFF, connect the harness connector at the driver window switch.
  7. Ignition OFF, disconnect the passenger window switch.
  8. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal A and ground.
  9. If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
  10. Ignition OFF, test for less than 1 ohm of resistance between the control circuit terminal H and ground.
  11. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the driver window switch.
  12. Ignition OFF, test for less than 1 ohm of resistance between the control circuit terminal D and ground.
  13. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the driver window switch.
  14. Connect a test lamp between control circuit terminal H and control circuit terminal D.
  15. Ignition ON, command the passenger door window UP and DOWN by pressing the passenger window control on the driver window switch. The test lamp should illuminate during either of the commands.
  16. If the test lamp remains OFF, test for a short to ground or an open/high resistance on either control circuit. If all circuits test normal, test or replace the driver window switch.
    If all circuit test normal, test or replace the driver window motor.
  17. Ignition OFF, reconnect the passenger window switch.
  18. Ignition OFF, disconnect the harness connector at the passenger window switch.
  19. Connect a test lamp between control circuit terminal A and control circuit terminal B.
  20. Ignition ON, command the appropriate window UP and DOWN by pressing the appropriate window switch. The test lamp should turn ON when commanding the UP and DOWN states.
  21. If the test lamp remains OFF during either of the commands, test for a short to ground on either control circuit. If the circuits test normal, test or replace the appropriate window switch.
  22. If all circuits test normal, test or replace the appropriate window motor.

Component Testing

Driver Window Switch

  1. Ignition OFF, disconnect the harness connector at the driver window switch.
  2. Test for infinite resistance between the signal terminals A and D and the B+ circuit terminal C with the passenger window switch in the INACTIVE position.
  3. If less than infinite resistance, replace the driver window switch.
  4. Test for less than 2 ohms of resistance between the signal terminal A and the B+ circuit terminal C with the passenger window switch in the UP position.
  5. If greater than 2 ohms, replace the driver window switch.
  6. Test for less than 2 ohms of resistance between the signal terminal D and the B+ circuit terminal C with the passenger window switch in the DOWN position.
  7. If greater than 2 ohms, replace the driver window switch.
  8. Test for infinite resistance between the signal terminals G and H and the B+ circuit terminal C with the driver window switch in the INACTIVE position.
  9. If less than infinite resistance, replace the driver window switch.
  10. Test for less than 2 ohms of resistance between the signal terminal G and the B+ circuit terminal C with the driver window switch in the UP position.
  11. If greater than 2 ohms, replace the driver window switch.
  12. Test for less than 2 ohms of resistance between the signal terminal H and the B+ circuit terminal C with the driver window switch in the DOWN position.
  13. If greater than 2 ohms, replace the driver window switch

Passenger Window Switch

  1. Ignition OFF, disconnect the harness connector at the passenger window switch.
  2. Test for infinite resistance between the signal terminals G and F and the B+ circuit terminal A with the switch in the INACTIVE position.
  3. If less than infinite resistance, replace the passenger window switch.
  4. Test for less than 2 ohms of resistance between the signal terminal G and the B+ circuit terminal A with the switch in the UP position.
  5. If greater than 2 ohms, replace the passenger window switch.
  6. Test for less than 2 ohms of resistance between the signal terminal F and the B+ circuit terminal A with the switch in the DOWN position.
  7. If greater than 2 ohms, replace the passenger window switch.

Window Motor

  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.
  2. If the function does not perform as specified, replace the appropriate Window Motor.
  3. Reverse the jumper wires; the appropriate window motor should perform the DOWN or UP function.
  4. 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.

    •  Front Side Door Window Switch Replacement - Left Side
    •  Front Side Door Window Switch Replacement - Right Side
    •  Front Side Door Window Regulator Motor Replacement