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

Battery voltage is applied at all times to the coil and switch terminals of the ACCESSORY relay located in the body control module (BCM). When the ignition is placed in the RUN or ACCESSORY positions, or if retained accessory power (RAP) is active, the BCM grounds the accessory relay coil. This energizes the accessory relay, closing the switch side contacts and provides battery voltage to the WINDOWS fuse through to the driver and passenger power window switches. The power window motor control circuits are connected to ground through the normally closed up and down switch contacts of the power window switches. When a power window switch is placed in the down position, the power window motor down control circuit is switched to 12 volts. The power window motor up control circuit serves as ground and the window travels down. By placing the power window switch in the up position, the polarity of the power window motor is reversed and the window travels up.

Circuit/System Testing

Power Windows Inoperative - All
1. Ignition OFF, disconnect the driver power window switch.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit and ground.

• If the test lamp does not illuminate, repair the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

3. Verify that a test lamp illuminates between the ignition circuit and the ground circuit at the driver power window switch harness connector.

• If the test lamp does not illuminate, repair the ground circuit for a short to voltage or an open/high resistance.

4. If all circuits test normal, test or replace the driver power window switch.

Power Window Inoperative - Driver
1. Ignition OFF, disconnect the driver power window switch.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit and ground.

• If the test lamp does not illuminate, repair the ignition circuit for an open/high resistance. If the circuit tests normal, replace the BCM.

3. Ignition OFF, reconnect the driver power window switch.
4. Disconnect the driver power window motor.
5. Connect a test lamp between the driver power window motor up and down control circuits at the driver power window motor harness connector.
6. Ignition ON, activate the driver power window switch to the up and down positions. The test lamp should illuminate as the driver power window switch is cycled between up and down.

• If the test lamp does not illuminate, repair the driver power window motor up and down control circuits for an open/high resistance. If the circuits test normal, test or replace the driver power window switch.

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

Power Window Inoperative - Passenger
1. Ignition OFF, disconnect the passenger power window switch.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit and ground.

• If the test lamp does not illuminate, repair the ignition circuit for an open/high resistance. If the circuit tests normal, replace the BCM.

3. Connect a test lamp between the power window master switch up and down control circuits at the passenger power window switch harness connector.
4. Activate the driver power window switch that controls the passenger window to the up and down positions. The test lamp should illuminate as the driver power window switch is activated to the up and down positions.

• If the test lamp does not illuminate, repair the power window master switch up and down signal circuits for an open/high resistance. If the circuits test normal, test or replace the driver power window switch.

5. Ignition OFF, reconnect the passenger power window switch.
6. Disconnect the passenger power window motor.
7. Connect a test lamp between the passenger power window motor up and down control circuits at the passenger power window motor harness connector.
8. Ignition ON, activate the passenger power window switch to the up and down positions. The test lamp should illuminate as the passenger power window switch is cycled between up and down.

• If the test lamp does not illuminate, repair the passenger power window motor up and down control circuits for an open/high resistance. If the circuits test normal, test or replace the passenger power window switch.

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

Power Window Inoperative - Express Down
1. Power window inoperative in the express down function is the result of an internal circuit failure of the driver power window switch.
2. Replace the driver power window switch.

Repair Instructions

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

* Front Side Door Window Regulator Replacement
* Window Switch Replacement
* Control Module References for BCM replacement, setup, and programming Programming and Relearning