WARNING: This page is about a different car, the 2008 GMC Sierra and 2008 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Module Power, Ground and Serial Data
Courtesy of GENERAL MOTORS CORP.
Fig 2: Shift Controls
Courtesy of GENERAL MOTORS CORP.
Fig 3: Pressure and Temperature Controls
Courtesy of GENERAL MOTORS CORP.
Fig 4: PNP Signals, VSS Signal and Tow/Haul Signal