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Power Windows Malfunction




Power Windows Malfunction (Sedan, Wagon)

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic procedure.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provide an overview of each diagnostic category.

Diagnostic Fault Information





Circuit/System Description

The front and rear power windows are controlled by the driver door lock/window switch and passenger door lock/window switch. The driver door lock/window switch and passenger door lock/window switch each contain power window switches that are integrated into the module. The driver door lock/window switch contains the master power window switches that control all power window operations. The power window switch contained in the passenger door lock/window switch controls the front passenger window operation only.

When the driver power window switch is activated to a desired position, the driver door lock/window switch examines the request and checks for messages from other vehicle control modules prohibiting window movement. If no prohibitive messages have been received, the driver door lock/window switch will send a serial data message to the driver door window motor to move the window to the desired position.

When the driver door lock/window switch receives a request to operate the right side passenger windows from the master switch, a serial data message is sent to the passenger door lock/window switch. The passenger door lock/window switch examines the request and checks for messages from other vehicle control modules prohibiting the window movement. If no prohibitive messages have been received, the passenger door lock/window switch will send a serial data message to the appropriate window motor to move the window as requested.

When the driver door lock/window switch receives a request to operate a rear window from the master switch, a serial data message is sent to the BCM. The BCM examines the request and checks for messages from other vehicle control modules prohibiting the window movement. If no prohibitive messages have been received, the BCM will send a serial data message to the appropriate rear window switch which will command the window motor as requested.

Reference Information

Schematic Reference
* Moveable Window Schematics (Electrical Diagrams)
* Door Control Module Schematics (Door Control Module Schematics)

Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Power Windows Description and Operation (Power Windows)

Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Ignition ON, observe the scan tool Driver Window RF Switch, Driver Window LR Switch and Driver Window RR Switch parameters while using the window switches on the S84D door lock/window switch-driver. The parameter should change between Off, Up, Down, and Express Down.

• If the values do not change, refer to Driver Window Switch Malfunction.

2. Command the M74D window motor-driver UP and DOWN with a scan tool, the M74D window motor-driver should perform the UP and DOWN functions.

• If the driver window does not perform as specified, refer to Front Window Motor Malfunction.

3. Observe the scan tool passenger window switch parameters while using the S84P door lock/window switch-passenger. The parameter should change between Off, Up, Down, Express Up and Express Down.

• If the values do not change, refer to Passenger Window Switch Malfunction.

4. Command the M74P window motor-passenger UP and DOWN with a scan tool, the M74P window motor-passenger should perform the UP and DOWN functions

• If the M74P window motor-passenger does not perform as specified, refer to Front Window Motor Malfunction.

5. Command the M74LR window motor-left rear and M74RR window motor-right rear UP and DOWN by using the window switches on the S84D door lock/window switch-driver. The M74LR window motor-left rear and M74RR window motor should perform the UP and DOWN functions from each switch.

• If either M74 window motor-rear does not perform as specified, refer to Rear Window Malfunction.

6. Command the M74LR window motor-left rear UP and DOWN by using the S79LR window switch-left rear. The M74LR window motor-left rear should perform the UP and DOWN functions.

• If the M74LR window motor-left rear does not perform as specified, refer to Rear Window Malfunction.

7. Command the M74RR window motor-right rear UP and DOWN by using the S79RR window switch-right rear. The M74RR window motor-right rear should perform the UP and DOWN functions.

• If the M74RR window motor-right rear does not perform as specified, refer to Rear Window Malfunction.

8. Observe the scan tool Window Lockout Switch parameter while pressing and depressing the window lockout switch on the S84D door lock/window switch-driver. The parameter should change between On and Off.

• If the value does not change between commanded states, replace the S84D door lock/window switch-driver.

9. Command the express up and express down functions of the driver and passenger door windows by pressing their window switches past the first detent and releasing and pulling their window switches past the first detent and releasing. The appropriate window should perform the express up and express down function.

• If the function does not perform as specified, refer to Window Regulator Motor Programming and Setup (Testing and Inspection).

Circuit/System Testing

Driver Window Switch Malfunction
1. Ignition OFF, disconnect the X1 harness connector at the S84D door lock/window switch-driver.
2. Test for less than 30 ohm between the ground circuit terminal 6 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 4 and ground.

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

4. Ignition OFF, connect the X1 harness connector at the S84D door lock/window switch-driver.
5. Ignition ON, observe the scan tool Driver LF Window Switch parameters while using the S84D door lock/window switch-driver. The parameter should change between Off, Up, Down, Express Up, and Express Down.

• If the value does not change between commanded states, replace the S84D door lock/window switch-driver.

6. If all circuits test normal, replace the S84D door lock/window switch-driver

Passenger Window Switch Malfunction
1. Ignition OFF, disconnect the X1 harness connector at the appropriate S84P door lock/window switch-passenger.
2. Test for less than 30 ohm between the ground circuit terminal 6 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 4 and ground.

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

4. Ignition OFF, connect the X1 harness connector at the S84P door lock/window switch-passenger.
5. Ignition ON, observe the scan tool Passenger Window Switch parameters while using the S84P door lock/window switch-passenger. The parameter should change between Off, Up, Down, Express Up, and Express Down.

• If the value does not change between commanded states, replace the S84P door lock/window switch-passenger.

6. If all circuits test normal, replace the S84P door lock/window switch-passenger.

Front Window Motor Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate front M74 window motor.
2. Test for less than 30 ohm between the ground circuit terminal 4 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 3 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 5-10V between the serial data circuit terminal 5 and ground.

• If less than the specified range, test the serial data circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the S84 door lock/window switch.

• If greater than the specified range, test the serial data circuit for a short to voltage. If the circuit tests normal, replace the S84 door lock/window switch.

5. If all circuits test normal, replace the front M74 window motor.

Rear Window Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate S79 window switch-rear.
2. Test for less than 30 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 H and ground.

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

Note: Check the rear window lockout switch on the S84D door lock/window switch-driver and verify the rear window switches are enabled.

4. Test for greater than 9 V between the control circuit terminal D and ground.

• 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 K9 BCM.

5. Test for greater than 9 V between the signal circuit terminal B and ground while commanding the rear window DOWN by using the window switch on the S84D door lock/window switch-driver.

• If less than the specified range, test the signal circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K9 BCM.

6. Test for greater than 9 V between the signal circuit terminal C and ground while commanding the rear window UP by using the window switch on the S84D door lock/window switch-driver.

• If less than the specified range, test the signal circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K9 BCM.

7. Ignition OFF, connect the S79 window switch-rear and disconnect the harness connector at the M74 window motor-rear.
8. Connect a test lamp between the control circuit terminal A and control circuit terminal B.
9. Ignition ON, command the rear window UP and DOWN by using the S79 window switch-rear. The test lamp should illuminate 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 S79 window switch-rear.

• If the test lamp is always ON, test either control circuit for a short to voltage. If the circuits test normal, replace the S79 window switch-rear.

10. If all circuits test normal, test or replace the M74 window motor-rear.

Component Testing

Rear Window Motor
1. Ignition OFF, disconnect the harness connector at the appropriate M74 window motor-rear.
2. Install a 25A fused jumper wire between one of the control terminals and 12V. Momentarily install a jumper wire between the other control terminal and ground. Reverse the jumper wires at least two times, the M74 window motor-rear should perform the UP and DOWN functions.

• If it does not perform as specified, replace the M74 window motor-rear.

Repair Instructions

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

* Front Side Door Window Regulator Motor Replacement (Sedan/Wagon) (Service and Repair)Front Side Door Window Regulator Motor Replacement (Coupe) (Service and Repair)
* Rear Side Door Window Regulator Motor Replacement (Rear Side Door Window Regulator Motor Replacement)
* Rear Side Door Window Switch Replacement (Sedan and Wagon) (Rear Side Door Window Switch Replacement)
* Control Module References (Programming and Relearning) for BCM, driver door lock/window switch, or passenger door lock/window switch replacement, setup, and programming

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