The power sunroof system consists of the following components:

The overhead console has a sunroof switch that controls both the vent and slide open options.

The sunroof glass may be moved by the use of the sunroof switch to any of the following positions:

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

The sunroof module determines sunroof motor direction based on inputs received from the sunroof switch. 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 system. 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 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 to tell the sunroof module that the glass is parallel to the roof. The limit switch only supplies open circuits or grounds to the module. An internal pull-up resistor in the sunroof module, connected to battery voltage, supplies the voltage at each input when the switch contacts are open.

The sunroof may be opened to this position by pressing and releasing the sunroof switch to the rearward position. This will apply the sunroof switch low reference circuit to the sunroof switch open signal circuit 12-volt reference input, pulling the reference voltage to 0 volts. The sunroof module seeing the 0 volt input, will apply voltage to the motor outputs, automatically sliding the sunroof glass and sunshade to the fully open position and allowing the wind deflector to raise upward. The motor will slide the sunroof glass until:

Closing the sunroof from the open position, the sunroof switch must be pressed and held forward until closed. As the close mode is initiated, the sunroof switch low reference circuit is applied to both the sunroof switch open vent signal circuit 12-volt reference and sunroof switch vent signal circuit 12-volt reference inputs, pulling them to 0 volts. As long as the sunroof switch is held to the close position the sunroof module will control voltage to the motor outputs to slide the glass to the closed position. The motor will run until the sunroof limit switch closes, applying the sunroof limit switch low reference circuit to the sunroof limit switch soft stop signal circuit 12-volt reference input, pulling the reference voltage to 0 volts, indicating the closed position has been reached. The wind deflector will retract prior to the sunroof glass reaching the fully closed position. To close the sunshade, this will have to be manually slid forward.

The vent open mode is initiated by pressing and held upward on the front portion of the sunroof switch. This will constantly apply the sunroof switch low reference circuit to the sunroof switch open vent signal circuit 12-volt reference input, pulling the reference voltage to 0 volts. As the sunroof module sees the constant input, it will apply voltage to the motor outputs, raising the rear of the sunroof glass to the full vent position. The motor will tilt the rear of the glass upward until it reaches a hard stop, that causes motor internal circuit breaker to open, stopping the motor. To stop the sunroof glass other than at the full vent position, release the sunroof switch when it reaches the desired position. To open the sunshade, this will have to be manually slid open.

Closing the sunroof from the vent position, the sunroof switch must be pulled downward once. This will initiate an express close operation. As the close mode is initiated, the sunroof switch low reference circuit is applied to both the sunroof switch open vent signal circuit 12-volt reference and sunroof switch vent signal circuit 12-volt reference inputs, pulling them to 0 volts. The sunroof module will control voltage to the motor outputs to lower the glass to the closed position, same direction as express opening. The motor will run until the sunroof limit switch closes, applying the sunroof limit switch low reference circuit to the sunroof limit switch soft stop signal circuit 12-volt reference input, pulling the reference voltage to 0 volts, indicating the closed position has been reached. To close the sunshade, this will have to be manually slid closed.

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:

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

If either the sunroof switch open signal circuit or sunroof switch open vent signal circuit closed for more than 30 seconds, the sunroof module considers the switch a stuck switch. In this case, the switch input is ignored by the sunroof module until the switch is opened or the power is cycled to the module. Under these conditions only, the sunroof is allowed to close from any position. Once the closed position is obtained, no further sunroof operation is allowed until the stuck switch is opened or the power is cycled to the module.