GM Service Manual Online
For 1990-2009 cars only

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit/System Description

The power window/mirror switch supplies power when requested to the front power windows in conjunction with the power window control module (PWCM). The PWCM is a stand alone module, located beneath the instrument panel on the right hand side, it controls the driver and passenger front windows. No communications bus is connected to it, therefore there are no software diagnostics on this module. It is powered directly from the RAP relay, and connected to the window motors. All levels of vehicle have the express down function which is enabled when the power window switch is held down for longer than 0.4 of a second. Higher levels of vehicle also have an express up function which is enabled when the power window switch is lifted for more than 0.4 seconds.

Reference Information

Schematic Reference

Moveable Window Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

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

Circuit/System Verification

  1. Verify that the Retained Accessory Power (RAP) circuit is functioning normally.
  2. If the RAP is not functioning normally refer to Retained Accessory Power (RAP) Description and Operation .

Circuit/System Testing

  1. Disconnect the power window/mirror switch harness connector.
  2. Verify less than 1 ohm of resistance from the ground circuit terminal and ground.
  3. If the resistance is greater than the specified value, repair the ground circuit for an open/high resistance.
  4. Ignition ON, test for 12 volts between the RAP fuse supply voltage circuit terminal X2-1 and ground.
  5. If the voltage is not between 9-16 volts, repair the RAP fuse supply voltage circuit for an open/high resistance.
  6. Ignition OFF, disconnect the PWCM harness connector.
  7. Verify less than 1 ohm of resistance from the ground circuit terminal 5 and ground.
  8. If the resistance is greater than the specified value, repair the ground circuit for an open/high resistance.
  9. Ignition ON, test for 12 volts between the RAP fuse supply voltage circuit terminal 8 and ground.
  10. If the voltage is not between 9-16 volts, repair the RAP fuse supply voltage circuit for an open/high resistance.
  11. Ignition OFF, connect a fused jumper wire from the ground circuit terminal 5 to the open return circuit terminal 10 at the PWCM harness connector.
  12. Connect a fused jumper wire from the open input circuit terminal 9 to the open signal circuit terminal 1 at the PWCM harness connector.
  13. Ignition OFF, connect the power window/mirror switch harness connector.
  14. Ignition ON, press the right front window switch to the Down position and verify that the window opens.
  15. If the window does not open perform the Window Motor Circuit Test.
    If the window opens replace the PWCM.

Window Motor Circuit Test

  1. Ignition OFF, disconnect the PWCM harness connector.
  2. Ignition ON, test for 12 volts between the circuit terminal 8 and ground.
  3. If the voltage is not between 9-16 volts, repair the RAP fuse supply voltage circuit for an open/high resistance.
  4. Connect a fused jumper wire from the open input circuit terminal 8 to the open signal circuit terminal 1 at the PWCM harness connector.
  5. Connect a fused jumper wire from the ground circuit terminal 5 to the open signal circuit terminal 10 at the PWCM harness connector.
  6. If the window motor does not operate, check if the motor operates in the reverse.
  7. Connect a fused jumper wire from the open input circuit terminal 8 to the open signal circuit terminal 10 at the PWCM harness connector.
  8. Connect a fused jumper wire from the ground circuit terminal 5 to the open signal circuit terminal 1 at the PWCM harness connector.
  9. If the window motor opens/closes, replace the power window/mirror switch.
  10. Test the power/ground supply circuits from the PWCM to the window motor for a short to ground, short to voltage or an open/high resistance.
  11. If all circuits test normal, replace the window motor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Power Mirror Switch Replacement
    •  Front Side Door Window Regulator Motor Replacement .
    •  Front Door Module Replacement .