For 1990-2009 cars

### Diagnostic Instructions

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

• | 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 | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
B+ | 1, 2 | 1, 2 | -- | --
Ignition | 1, 2 | 1, 2 | -- | --
Sunroof Switch Close Signal | 1 | 1 | 1* | --
Sunroof Switch Open Signal | 1 | 1 | 1* | --
Sunshade Switch Close Signal | 2 | 2 | 2* | --
Sunshade Switch Open Signal | 2 | 2 | 2* | --
Sunroof Switch Low Reference | -- | 1 | -- | --
Sunshade Switch Low Reference | -- | 2 | -- | --
Sunroof Module Ground | -- | 1 | -- | --
Sunshade Module Ground | -- | 2 | -- | --
* Internal damage to the sunroof switch may occur if shorted to B+ 1. Power Sunroof Malfunction 2. Power Sunshade Malfunction

### 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 circuit in the sunroof switch.

### Reference Information

#### Schematic Reference

Sunroof Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Sunroof Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

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

⇒ | If the sunroof does not open, refer to Power Sunroof Malfunction.

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

⇒ | If the sunroof does not close, refer to Power Sunroof Malfunction.

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

⇒ | If the sunroof does not vent open, refer to Power Sunroof Vent Malfunction.

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

⇒ | If the sunroof does not close, refer to Power Sunroof Vent Malfunction.

### Circuit/System Testing

Important: Because of the accessibility of the sunroof switch and the sunshade switch, perform the sunroof/sunshade switch component test before beginning the Circuit/System Testing.

#### Power Sunroof Malfunction

1. Ignition OFF, disconnect the harness connector at the sunroof or sunshade module.
2. Test for less than 5.0 ohm 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, refer to Retained Accessory Power Malfunction.

5. Connect the harness connector at the sunroof or sunshade module.
6. Disconnect the harness connector at the sunroof or sunshade switch.
7. Test for less than 5.0 ohm 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.

When performing the following tests, make sure that the sunroof or sunshade is not at its end of 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 signal circuit for a short to ground, short to voltage or an open/high resistance. If the circuit test is normal, replace the appropriate 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 signal circuit for a short to ground, short to voltage or an open/high resistance. If the circuit test is normal, replace the appropriate module.

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

#### Power Sunroof Vent Malfunction

1. Perform the Sunroof Motor/Actuator Initialization/Teach Process.
2. With the sunroof in the closed position, press the sunroof vent open switch. The sunroof should vent open.

⇒ | If the sunroof does not vent open, replace the sunroof control module.

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

⇒ | If the sunroof does not close, replace the sunroof control module.

### Component Testing

#### Sunroof/Sunshade Switch

1. With the ignition OFF, disconnect the harness connector at the appropriate switch.
2. Test for infinite resistance between the switch terminals listed below and the ground terminal B with the switch in the open position.

• | Roof/shade open terminal D

• | Roof/shade close terminal E

⇒ | If not the specified value, replace the appropriate switch.

Important: If the switch tests open in any switch position other than Off, test the sunroof switch signal circuits for a short to voltage before replacing the switch.

3. Test for less than 5.0 ohms of resistance between the switch terminals listed below and the ground terminal B with the switch in the appropriate position.

• | Roof/shade open terminal D

• | Roof/shade close terminal E

⇒ | If greater than the specified range, replace the appropriate switch.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Sunroof Switch Replacement

• | Control Module References for BCM, sunroof control module, or sunroof shade module replacement, setup, and programming