GM Service Manual Online
For 1990-2009 cars only

Power Sunroof System Components

The power sunroof system (CF5) consists of the following components:

    • The combined sunroof switch/actuator/motor.
    • The sunroof glass.
    • The manually operated sunshade.
    • The rail and track assembly upon which the sunroof glass rides.
    • Power supply for the sunroof module; SUNROOF 20 A, fuse 25 (memory for the sunroof actuator) and the CLAMP 15 CRUISE 15 A, fuse 15.
    • Door jamb switch inputs to control the retained accessory power feature internal to the sunroof actuator.
    • Ground G103.

The power sunroof will operate with the ignition switch in ON and for an unlimited amount of time once the ignition switch is turned to OFF, until any door is open. The sunroof actuator has it's own internal retained accessory power type feature. Once the sunroof actuator detects the sunroof ignition supply missing (ignition OFF), the actuator will still allow continuation of sunroof operation. The sunroof will be operational until a low signal is detected on the door open signal circuit. Any door opened at this time will disable further operation of the sunroof, until the ignition cycle is activated again.

The power sunroof is electrically operated from a rotary switch that is part of the sunroof actuator. The rotary switch is located in the center of the windshield header area. The sunroof switch being a rotary (potentiometer) type switch will allow the sunroof glass not only to be able to move to the positions listed below, but to any position in between:

    • Express Open
    • Express Fully Close
    • Express Vent Open

Express Open

To open the power sunroof, turn ignition to ON, rotate the sunroof switch clockwise to the last setting. The sunroof switch (a potentiometer), which is part of the sunroof module, sends a position signal to the sunroof module. The sunroof actuator checks the position of the power sunroof using the potentiometer's signal and drives the motor to move the sunroof to match the new switch setting. The sunroof glass will slide open, in between the roof and the headliner, allowing the wind deflector to raise upward. As the sunroof glass slides open so will the sunshade. During this operation you can turn the sunroof switch to any other position to stop the glass in a desired position.

Express Fully Close

To close the power sunroof, rotate the sunroof switch counterclockwise so it faces towards the front of the vehicle. The sunroof switch sends a position signal to the sunroof module. The sunroof actuator checks the position of the power sunroof using the potentiometer's signal and drives the motor to move the sunroof to match the new switch setting. The sunroof glass will slide to the fully closed position unless the switch is rotated to a position other than fully closed to stop the glass in a desired position. As the sunroof glass nears the fully closed position, the wind deflector will be forced downward. To close the sunshade, this will have to be manually slid forward.

Express Vent Open

To open the power sunroof to the vent position, rotate the sunroof switch counterclockwise until it stops. The sunroof switch sends a position signal to the sunroof module. The sunroof actuator checks the position of the power sunroof using the potentiometer's signal and drives the motor to move the sunroof to match the new switch setting. The rear of the sunroof glass will raise slightly to the vent position. To open the sunshade, this will have to be manually slid open.

Sunroof Motor

The sunroof has a bi-directional motor. When the motor is not operating both circuits are grounded. When the motor drives the sunroof glass in the direction from the vent position to the closed position then to the open position, the following occurs:

    • Voltage is supplied to the sunroof motor open circuit.
    • Ground is maintained to the sunroof motor close circuit.

When the motor drives the sunroof in the direction from the open position to the closed position then to the vent position, the following occurs:

    • Voltage is supplied to the sunroof motor close circuit.
    • Ground is maintained to the sunroof motor open circuit.

The sunroof actuator is equipped with a timer circuit which stops the operation of the sunroof motor after 8 seconds.

Anti-Pinch Guard

If an object is in the way of the sunroof glass while closing, the sunroof glass will stop and depending on the position of the sunroof glass, it may reverse back open to a preset factory position.

To temporarily disable the anti-pinch guard, press upward on the sunroof switch as it is closing. This will override the system, allowing the window to continue to close. Once the switch is released the anti-pinch feature is enabled.

Vehicle Speed Signal

The Vehicle Speed Signal (VSS) circuit to the sunroof actuator is used to assist in the closing of the sunroof glass while driving. When requesting to close the sunroof glass while driving at high speeds, the sunroof actuator will compensate for the resistance against the sunroof glass. If there is no VSS signal and the sunroof actuator detects a resistance in the sunroof glass closure, the sunroof actuator may stop and reverse back (see Anti-Pinch Guard).

Power Loss

If the battery has been disconnected or if the battery requires to be recharged, the sunroof actuator will need to be reprogrammed. Anytime the sunroof actuator loses power, the actuator loses its memory. For programming the sunroof module, refer to Sunroof Motor Synchronization .

The sunroof can be closed manually if a failure in the power supply occurs or if the sunroof cannot be closed by using the sunroof switch. Refer to Sunroof Manual Operation .

Scan Tool Usage

The sunroof actuator can also be operated by using the scan tool. When the scan tool is installed and communication has been established, the technician can use the scan tool to operate the sunroof module. For parameters and an explanation, refer to Scan Tool Data List and Scan Tool Data Definitions .