WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Power, Ground, Indicators and Passenger Presence Sensor Schematic
Courtesy of GENERAL MOTORS CORP.
Fig 2: Front Air Bags Front End Sensors, Seat Belt Pretensioners and Seat Position Sensor Schematic
Courtesy of GENERAL MOTORS CORP.
Fig 3: Roof Rail Modules, Side Impact Air Bags and Side Impact Sensors Schematic