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Power Sunroof Malfunction




Power Sunroof Malfunction

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 approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions)provides an overview of each diagnostic category.

Diagnostic Fault Information





Circuit/System Description

Ignition voltage is applied to the sunroof switch via the S ROOF fuse. The sunroof switch provides voltage and ground to the sunroof motor when the switch is activated. The position of the sunroof switch determines which sunroof motor control circuits will receive voltage and which will receive ground.

Reference Information
Schematic Reference

Sunroof Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Sunroof Description and Operation (Description and Operation)
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)

Circuit/System Verification

1. With the sunroof in the closed position, press the sunroof vent switch. The sunroof should vent.

• If the sunroof does not vent refer to Sunroof System Test.

2. With the sunroof in the closed position, press the sunroof open switch. The sunroof should open.

• If the sunroof does not open refer to Sunroof System Test.

3. With the sunroof in the open position, press the sunroof close switch. The sunroof should close.

• If the sunroof does not close refer to Sunroof System Test.

4. If all circuits test normal, test or replace the appropriate sunroof switch.

Circuit/System Testing
Sunroof System Test

1. Ignition OFF, disconnect the harness connector at the sunroof motor.
2. Test for less than 5.0 Ohms between the ground circuit terminal A and ground.

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

3. Test for infinite resistance between the control circuit terminal C and ground.

• If less than the specified value, test the control circuit for a short to ground. If the circuit tests normal, test or replace the sunroof switch.

4. Test for infinite resistance between the control circuit terminal D and ground.

• If less than the specified value, test the control circuit for a short to ground. If the circuit tests normal, test or replace the sunroof switch.

5. Disconnect the harness connector at the sunroof switch.
6. Test for less than 5.0 Ohms between the ground circuit terminal A and ground.

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

7. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal E and ground.

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

8. Connect the sunroof switch. Connect a test lamp between control circuit terminal C and ground.
9. Press and release the sunroof close switch. The test lamp should turn ON and OFF.

• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, test or replace the sunroof switch.
• If the test lamp is always OFF, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the sunroof switch.

10. Connect a test lamp between control circuit terminal D and ground.
11. Press and release the sunroof open switch. The test lamp should turn ON and OFF.

• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, test or replace the sunroof switch.
• If the test lamp is always OFF, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the sunroof switch.

12. Connect a test lamp between control circuit terminal B and ground.
13. Press and release the sunroof vent switch. The test lamp should turn ON and OFF.

• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, test or replace the sunroof switch.
• If the test lamp is always OFF, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the sunroof switch.

14. If all circuits test normal, replace the sunroof motor.

Component Testing

Sunroof Switch
1. Ignition OFF, disconnect the harness connector at the sunroof switch.
2. Test for infinite resistance between the following control circuits and the ignition circuit terminal E.

* Ground circuit terminal A
* Control circuit terminal B
* Control circuit terminal C
* Control circuit terminal D

• If less than the specified range, replace the sunroof switch.

3. Test for infinite resistance between the following control circuits and the ground circuit terminal A.

* Control circuit terminal B
* Control circuit terminal C
* Control circuit terminal D
* Ignition circuit terminal E

• If less than the specified range, replace the sunroof switch.

4. While holding the sunroof switch button to OPEN, test for less than 1 Ohms between the following circuits.

* Control circuit terminal C and ground circuit terminal A
* Control circuit terminal D and the ignition circuit terminal E

• If greater than the specified range, replace the sunroof switch.

5. While holding the sunroof switch button to VENT, test for less than 1 Ohms between the following circuits.

* Control circuit terminal D and the ignition circuit terminal E
* Control circuit terminal C and control circuit terminal B

• If greater than the specified range, replace the sunroof switch.

6. While holding the sunroof switch button to CLOSE, test for less than 1 Ohms between the following circuits.

* Control circuit terminal D and ground circuit terminal A
* Control circuit terminal C and the ignition circuit terminal E

• If greater than the specified range, replace the sunroof switch.

Sunroof Motor

Note: When performing the following tests, make sure that the sunroof is not at its end of travel position by switching the jumper wires to the other control circuits if the sunroof did not move in one direction.

1. Ignition OFF, disconnect the harness connector at the sunroof motor.
2. Install a 15-amp fused jumper wire between the control terminal C and 12 volts. Momentarily install a jumper wire between the control terminal D and ground. The sunroof should OPEN or CLOSE.

• If the function does not perform as specified, replace the sunroof motor.

3. Reverse the jumper wires. The sunroof motor should go in the opposite direction as step 2.

• If the function does not perform as specified, replace the sunroof motor.

Repair Instructions

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

* Sunroof Motor/Actuator Replacement (Sunroof Motor/Actuator Replacement)
* Sunroof Switch Replacement (Service and Repair)

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