To Close from Vent Position
WARNING: This page is about a different car, the 2002 Buick Regal and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
To close the power sunroof from the vent position, turn the ignition ON, with the engine OFF. Press and hold the rearward portion of the sunroof switch. 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 of 0 volts at the sunroof switch open signal circuit input, the sunroof glass will continue to lower downward to the closed position. The sunroof glass will soft stop at the closed position based on the inputs from the sunroof limit switches. The sunshade will have to be manually slid closed.