Power Sunroof Malfunction

Power Sunroof 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.

Circuit/System Description

The sunroof and sunshade modules supply each of the switch signal circuits with a 12-volt reference. When a switch is pressed the signal circuit is pulled low signaling the sunroof or sunshade open or close request. The modules determine the motor direction based on inputs received from the overhead console sunroof switches. When the modules reverse the polarity of the applied voltage, the motors reverse direction. Ignition voltage is supplied to the sunroof and sunshade modules by the BCM. B+ is applied to the sunroof and sunshade modules via the S/ROOF/SUNSHADE fuse.

Diagnostic Aids

A short to B+ on any of the sunroof switch signal circuits will open the ground trace in the sunroof switch.

Circuit/System Testing

1. Ignition OFF, disconnect the appropriate sunroof or sunshade module harness connector.
2. Test for less than 1.0 ohm of resistance between the ground circuit terminal 1 and ground.

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

3. Verify that a test lamp illuminates between the B+ circuit terminal 6 and ground.

^ If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, replace the fuse and determine if the sunroof or sunshade module is causing the fuse to open. Replace the appropriate module.

4. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 3 and ground.

^ If the test lamp does not illuminate, test the ignition circuit for an open/high resistance. If the circuit tests normal, replace the body control module.

5. Connect the sunroof and sunshade modules.
6. Disconnect the appropriate sunroof or sunshade switch.
7. Test for less than 1.0 ohm of resistance between the ground circuit terminal B and ground.

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

Important: Apply ground to the module for no longer than 2 seconds at a time or the module could be damaged.

Important: When performing the following tests, make sure that the sunroof or sunshade is not at its end if travel position by switching the grounded jumper to the other signal circuit if the sunroof or sunshade did not move in one direction.

8. Momentarily install a 10-amp fused jumper wire between the signal circuit terminal D and ground. The sunroof or sunshade should move.

^ If the sunroof or sunshade does not move, test the switch signal circuit for a short to ground, short to voltage or an open/high resistance. If the circuit test is normal, replace the inoperative module.

9. Momentarily install a 10-amp fused jumper wire between the signal circuit terminal E and ground. The sunroof or sunshade should move.

^ If the sunroof or sunshade does not move, test the switch signal circuit for a short to ground, short to voltage or an open/high resistance. If the circuit test is normal, replace the inoperative module.

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

Repair Instructions

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

* Sunroof Switch Replacement