Vent Open
WARNING: This page is about a different car, the 2007 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.
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.