GM Service Manual Online
For 1990-2009 cars only

Power Sunroof System Components

The Power Sunroof System consists of the following components:

    • Sunroof control module
    • Sunroof switch
    • Sunroof glass, tilt-slide-vent style with glass sliding between the headliner and the roof panel
    • Rail and track assembly upon which the sunroof glass rides
    • Sunroof sunshade panel
    • SUNROOF Fuse 20 A
    • Ground G201

Power and Grounds

Battery positive voltage is supplied at all times to the sunroof control module from the 20 A SUNROOF fuse located in the instrument panel fuse block. Ground is supplied to the sunroof control module through the module ground circuit and G201.

Ground is supplied to the sunroof switch through the switch ground circuit and G201.

Power Sunroof Operation

The Power Sunroof System will operate only with the ignition turned to the RUN or Accessory positions. Once the ignition is turned OFF and the sunroof is open, the sunroof might automatically close.

The power sunroof is operated from the sunroof switch. The sunroof switch, when rotated to a selection, will send coded information to the sunroof control module as to what position the sunroof window is to move to. The sunroof control module will then command the motor to slide the sunroof glass to the requested position.

Sunroof Switch

The sunroof switch is a rotary dial type switch with four output signals to the sunroof control module. The coded inputs to the sunroof control module will initiate a request to open the sunroof window to a specific position. The sunroof switch is located in the dome light assembly. The sunroof switch positions are:

    • 6 sliding open positions
    • 3 vent positions
    • Flush close position
    • Emergency stop/resume position

Express Open

To express open the sunroof select any of the 6 express sliding open positions by rotating the sunroof switch clockwise. The sunroof switch will send a sunroof position request signal through the switch output signals to the sunroof control module. The sunroof control module will interpret the inputs and command the motor to slide the window to the specified requested position. The sunshade will slide open along with the window.

Express Fully Close

To express close the sunroof rotate the sunroof switch to the flush close position. The sunroof switch will send a sunroof position request signal through the sunroof switch output signals to the sunroof control module. The sunroof control module will interpret the inputs and command the motor to slide the window to the close position. The sunroof control module will continue to control the sunroof motor until the sunroof window reaches the flush close position. The sunshade panel will have to be manually slid closed.

Express Vent Open

To express open the sunroof to a vent position rotate the sunroof switch counterclockwise to any of the three vent selections. The sunroof switch will send a coded input through the sunroof switch output signals to the sunroof control module. The sunroof control module will interpret the inputs and command the motor to slide the window to the specified requested position. The sunshade panel will have to be manually slid open.

Emergency Stop

When the sunroof is performing an automatic open or automatic close operation, the automatic sliding action of the sunroof can be interrupted by pressing the sunroof switch upward. When the sunroof switch is pressed again, the sunroof will resume and complete the previous requested action.

Anti-Pinch Guard

If the sunroof encounters an obstruction when closing from a sliding position, it immediately returns to the fully open position. If the sunroof encounters an obstruction when closing from the vent position, it immediately returns to the fully open vent position. The sunroof will not operate again until the sunroof switch is pressed upwards or a different position is selected.

Power Sunroof Motor

The sunroof motor is a reversible drive permanent magnet DC motor. The sunroof control module manipulates the voltage polarity at the motor to achieve the different opening and closing positions.

Limit Switch

When closing the sunroof window from any vent position, the sunroof window drops slightly below the flush close position and returns, swiping the seal and coming to rest in the flush close position. When closing the sunroof window from any of the 6 sliding open positions, the sunroof module considers the position of the sunroof window and stops the sunroof window in the flush close position.