GM Service Manual Online
For 1990-2009 cars only

The interior trim panels are molded plastic and fasten with screws, bolts, or plastic clips.

Pressure Relief Vent

When all the windows are closed and the ventilation system is ON, the addition of outside air to the interior of the vehicle causes a positive pressure within the vehicle. In order to relieve the pressure, air is released through 2 pressure relief vents. The pressure relief vents are located at the rear quarter of the vehicle, behind the bumper fascia.