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For 1990-2009 cars only

Power Sunroof System Components

    • Sunroof control module
    • Sunroof motor, with limit switch
    • Sunroof switches
    • Sunroof glass
    • Rail and track assembly upon which the sunroof glass rides
    • S/ROOF Fuse 20-A
    • Ground G403

The sunroof module contains the logic for the opening and the closing of the sunroof. The sunroof motor assembly contains the reversible DC drive motor, the gear train, and the soft stop limit switch.

The sunroof module determines the sunroof motor direction based on inputs received from the overhead console sunroof switches. When the ignition switch is in the ON position or when retained accessory power (RAP) is active, voltage is applied to the sunroof module via the RAP relay. For a description and operation of the RAP system, refer to Retained Accessory Power (RAP) Description and Operation in Computer/Integrating Systems. The sunroof module controls the sunroof motor direction by changing the polarity of the applied voltage. The sunroof module remembers the sunroof position whenever the ignition switch is turned to the OFF position. The limit switch is used as an input to the sunroof module to indicate that the glass is fully closed, or in the comfort stop positions. The limit switch is grounded when the sunroof glass is in the fully closed or comfort stop positions, otherwise it is open.

Express Open

The EXPRESS OPEN mode is initiated by momentarily moving the sunroof slide switch (ROOF) rearward to the second position (EXPRESS OPEN). This applies a ground from the sunroof switch low reference circuit through both the sunroof switch open signal and the sunroof switch express signal circuits to the sunroof module. The sunroof module will then control voltage to the control circuits of the sunroof motor. The sunroof motor will run until the limit switch contacts are closed. The closing of the limit switch will apply the sunroof limit switch low reference circuit to the sunroof limit switch soft stop signal circuit to the sunroof module, indicating the comfort stop position has been reached. The comfort stop position is a predetermined position that the sunroof glass will open to allowing minimal wind noise. If the sunroof slide switch is pressed again, the sunroof motor will run until a mechanical stop is met in the sunroof track, indicating the fully open position. Also, the sunroof module will revert back to manual operation if the switch is not released within 1 second. As the sunroof is expressing open the wind deflector will raise upward and the sunshade will slide along with the glass.

Slide Close

The SLIDE CLOSE mode is initiated by moving and holding the sunroof slide switch (ROOF) forward. This applies a ground provided from the sunroof limit switch low reference circuit to the sunroof switch close vent signal input of the sunroof module. The sunroof module controls voltage to the control circuits of the sunroof motor. The sunroof motor will run until the limit switch contacts are closed. The closing of the limit switch will apply the sunroof limit switch low reference circuit to the sunroof limit switch soft stop signal circuit to the sunroof module, indicating the flush closed position has been reached. As the sunroof is approaching the close position the sunroof glass will force the wind deflector downward. The sunshade will have to be manually slid closed.

Slide Open

The SLIDE OPEN mode is initiated by moving and holding the sunroof slide switch (ROOF) rearward to the first position. This applies a ground from the sunroof switch low reference circuit through the sunroof switch open signal circuit to the sunroof module. The sunroof module controls voltage to the control circuits of the sunroof motor. The sunroof motor will run until the a mechanical stop is met in the sunroof track, indicating the fully open position. As the sunroof is opening the wind deflector will raise upward and the sunshade will slide along with the glass.

Vent Open

The VENT OPEN mode is initiated by pressing and holding the rear portion of the sunroof vent switch (VENT). This applies a ground from the sunroof switch low reference circuit through the sunroof switch open vent signal circuit to the sunroof module. The sunroof module controls voltage to the control circuits of the sunroof motor. The sunroof motor will run until a mechanical stop is met in the sunroof track, indicating the vent open position. The sunshade will need to be manually slid open.

Vent Close

The VENT CLOSE mode is initiated by pressing and holding the forward portion of the sunroof vent switch (VENT). This applies a ground from the sunroof switch low reference circuit through the sunroof switch close vent signal circuit to the sunroof module. The sunroof module controls voltage to the control circuits of the sunroof motor. The sunroof motor will run until the limit switch contacts are closed. The closing of the limit switch will apply the sunroof limit switch low reference circuit to the sunroof limit switch soft stop signal circuit to the sunroof module, indicating the flush closed position has been reached. The sunshade will need to be manually slid closed.

Limit Switch

The limit switch will only signal the sunroof module when the sunroof glass reaches the flush closed or the comfort stop positions, all other positions the switch is open. When the sunroof limit switch closes, the sunroof limit switch low reference circuit will be applied to the sunroof limit switch soft stop signal circuit to the sunroof module.

Stuck Switch

The sunroof system has a sunroof stuck switch feature that will allow a closing due to one of the sunroof switch signal circuits being shorted to ground or a faulty sunroof switch. If either the sunroof switch open, open vent or express signal circuits should become grounded, that sunroof signal circuit will input a low signal to the sunroof module. This will drive the sunroof window to the requested position. If the same signal circuit continues to remain low, as if a stuck sunroof switch or a short to ground, the sunroof module will ignore any other input request for 1 minute. After 1 minute, a request to close the sunroof window will be granted once the sunroof switch is pressed to the close position. The sunroof system will become inoperative once in the close position, until the ignition is cycled back on.