WARNING: This page is about a different car, the 2007 Pontiac Solstice. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Data Link, Ground, and Power Schematic
Courtesy of GENERAL MOTORS CORP.
Fig 2: Lighting System References Schematic
Courtesy of GENERAL MOTORS CORP.
Fig 3: Brakes, Cooling System, Cruise, and Door Lock References Schematic