WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Module Power, Ground & Serial Data Schematic
Courtesy of GENERAL MOTORS CORP.
Fig 2: Shift Controls Schematic
Courtesy of GENERAL MOTORS CORP.
Fig 3: Pressure & Temperature Controls Schematic
Courtesy of GENERAL MOTORS CORP.
Fig 4: PNP Signals, VSS Signal & Tow/Haul Signal Schematic