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For 1990-2009 cars only

Sunroof Description and Operation Before VIN 209983

The power sunroof (CF5 option) has the following features:

    • A manually operated sunshade. A recess is provided in the sunshade to be used to push the shade open or pull it shut.
    • An express module at the front of the sunroof module, allows the window panel to stop in the closed, vent and fully open positions.
    • The position encoding system (PES) module contains the limit switches for the window panel operation. Its gearing drives the window into the desired position. The window panel must be in the closed position when this unit is replaced.
    • The sunroof actuator attaches to the PES module and contains the driveshaft that drives the gearing in the PES. This driveshaft will turn infinitely in both directions.
    • The power sunroof switch is a 2 position rocker type switch which electrically operates the power sunroof. The switch is located in the headliner in front of the sunroof. Press and hold the front indent position to move the sunroof glass to the vent position. Press and hold rear indent and the sunroof will return to the full closed position.
        Press rear indent once and the sunroof glass will slide to the full open position automatically (express open).
        Press and hold the front indent position on the control switch in order to close the sunroof window from the open position. The switch must be held until the window reaches a desired position or until it closes completely.
    • A drain trough is positioned under the sunroof glass panel. Water is collected by this trough and is drained off by drain hoses connected at each corner.
    • The glass panel seal fits around the glass panel and is used to seal the opening between the glass panel and the roof panel.
    • The sunroof electrical harness is routed to join the body harness at the right rear pillar.

Power Sunroof System Components

The power sunroof system consists of the following components:

    • Actuator/motor
    • Sunroof control module
    • Sunroof limit switches (position encoding system [PES] module)
    • Sunroof switch
    • Sunroof glass (tilt/slide type, with glass sliding between roof and headliner)
    • Sunshade
    • Rail and track assembly upon which the sunroof glass rides
    • Power supply for the sunroof module: PWR WINDOWS PWR SUN ROOF 30 A circuit breaker
    • Ground from G402

Power Sunroof Operation

The power sunroof will operate with the ignition switch turned to Accessory or RUN. Once the ignition switch is turned to OFF the sunroof will continue to operate until any door is open or when the retained accessory power (RAP) has timed out. For a description and operation of the RAP system, refer to Retained Accessory Power (RAP) Description and Operation in Retained Accessory Power.

Use the rocker type sunroof switch, located in the front center of the headliner, to command the sunroof to :

    • Vent
    • Express open
    • Close

Pressing the sunroof switch (rearward portion), the sunroof glass will slide from:

    • Vent position to the closed position
    • Closed position to the open position

Pressing the sunroof switch (forward portion), the sunroof glass will slide from:

    • Open position to the closed position
    • Closed position to the vent position

To Vent Open

To open the power sunroof to the vent position from the closed position, turn the ignition to ON, with engine OFF. Press and hold the sunroof switch (forward portion). This will apply the sunroof switch low reference to the sunroof switch close signal circuit (5 volt reference) input to drop to 0 volts. As long as the sunroof module sees a constant input request from the sunroof switch close signal circuit (0 volts), the module will continue to raise the rear of the glass upward to the full vent position. The sunroof glass will stop (soft stop) at the full vent position based on the inputs from the limit switches. To stop the sunroof glass in a position other than the full vent position, release the sunroof switch when the sunroof glass reaches the desired vent position. The sunshade will have to manual slid open.

To Close from Vent Position

To close the power sunroof from the vent position, turn the ignition ON, with the engine OFF. Press and hold the sunroof switch (rearward portion). This will apply the sunroof switch low reference to the sunroof switch open signal circuit (5 volt reference) input to drop to 0 volts. As long as the sunroof module sees a constant input request from the sunroof switch open signal circuit (0 volts), the module will continue to lower the rear of the glass (downward) to the closed position. The sunroof glass will stop (soft stop) at the closed position based on the inputs from the limit switches. The sunshade will have to be manually slid closed.

Express Open

The express open will work only with the glass in between the closed and partially open positions. To express open the power sunroof, turn the ignition ON, with engine OFF. Press the sunroof switch (rearward portion) once (less than 1.5 seconds). This will apply the sunroof switch low reference to the sunroof switch signal open signal circuit (5 volt reference) input to drop to 0 volts momentarily. The momentary 0 volts input to the sunroof control module indicates an express open request. The sunroof glass will lower slightly, then begin to automatically slide (express open) between the roof and headliner, allowing the wind deflector to raise upward. The sunroof glass will stop (soft stop) at the full open position based on the inputs from the limit switches. As the sunroof glass expresses open so will the sunshade. To stop the sunroof glass in a desired position other than to the express open position:

    • As the sunroof is expressing open, press the sunroof switch again (in either direction) to stop the movement.
    • Instead of momentarily pressing the sunroof switch to express open, maintain pressing (more than 1.5 seconds) the sunroof switch (rearward portion). When the sunroof glass reaches the desired position, then release the switch.

To Close from Open Position

To close the power sunroof from the open position is the same as to opening the sunroof glass to the vent position. Turn the ignition ON, with the engine OFF. Press and hold the sunroof switch (forward portion). This will apply the sunroof switch low reference to the sunroof switch close signal circuit (5 volt reference) input to drop to 0 volts. As long as the sunroof module sees a constant input request from the sunroof switch close signal circuit (0 volts), the module will continue to slide the sunroof glass to the closed position. The sunroof glass will stop (soft stop) at the closed position based on the inputs from the limit switches. The sunshade will have to be manually slide closed.

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 to closed or closed to open position, the following occurs:

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

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

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

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

Limit Switches

The limit switches are part of the position encoding system (PES) that tracks the position of the glass through the limit switches and understands the limits (soft stops) of travel to the:

    • Full vent position
    • Full open position

The sunroof control module monitors the limit switches (PES). As a limit switch closes, the sunroof limit switch circuit 5 volt reference will be shorted to the sunroof limit switch low reference circuit, pulling the reference voltage to 0 volts. The sunroof control module understands the position of the sunroof glass based on the multiple input combinations through the limit switch inputs, which brings the sunroof glass to a soft stop when it reaches the full vent or full open positions and when it has reached the closed position.

Sunroof Maintenance

  1. Clean the surface of the window by wiping with a clean, dampened cloth using GM Window Cleaner GM P/N 10500427 or equivalent.
  2. Apply a silicone lubricant GM P/N 12345579 or equivalent (Canadian P/N 1974984) in order to perform the following functions:
  3. • Prolong the weatherstrip life
    • Help to seal the weatherstrip
    • Assist in eliminating squeaks

Sunroof Description and Operation ZRX/XTREME

Power Sunroof System Components

The power sunroof system consists of the following components:

    • Sunroof actuator motor
    • Sunroof switch
    • Sunroof window-spoiler type, with window sliding above the roof
    • Rail and track assembly upon which the sunroof window rides
    • Rear wiper 15 A
    • Ground G300

Power Sunroof Operation

The sunroof switch receives power through the accessory voltage circuit from the rear wiper fuse. The power sunroof will operate with the ignition switch turned to RUN. The sunroof switch also receives a constant ground from G300. Use the sunroof switch, located in the front center of the headliner, to command the sunroof window to:

    • Open
    • Close

To Open

Press and hold the rearward portion of the sunroof switch firmly, to the open position. The sunroof switch will apply the accessory voltage through to the sunroof motor open control circuit to the sunroof actuator motor. The sunroof switch will also supply the ground circuit to the sunroof motor close control circuit to the sunroof actuator motor. The rear edge of the sunroof window will raise upward and then slide rearward until it reaches a hard stop at the full open position, unless the sunroof switch is released.

To Close

Press and hold the forward portion of the sunroof switch to the close position. The sunroof switch will apply the accessory voltage through to the sunroof motor close control circuit to the sunroof actuator motor. The sunroof switch will also apply the ground circuit to the sunroof motor open control circuit to the sunroof actuator motor. The sunroof window will slide to the close position and will hard stop at the close position, unless the sunroof switch is released.

Sunroof Switch

The sunroof switch has three positions:

    • Close
    • Off, in rest position
    • Open

Pressing the forward portion of the sunroof switch will slide the sunroof window to the close position. Pressing the rearward portion of the sunroof switch will raise the rear edge of the sunroof window and then will move the sunroof window from the close position to the full open position, unless the switch is released.