WARNING: This page is about a different car, the 2010 GMC Sierra and 2010 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Module Power, Ground, Serial Data, and MIL
Courtesy of GENERAL MOTORS CORP.
Fig 2: 5-Volt and Low Reference
Courtesy of GENERAL MOTORS CORP.
Fig 3: Engine Data Sensors - Pressure and Temperature
Courtesy of GENERAL MOTORS CORP.
Fig 4: Engine Data Sensors - Heated Oxygen Sensors
Courtesy of GENERAL MOTORS CORP.
Fig 5: Engine Data Sensors - Throttle Controls
Courtesy of GENERAL MOTORS CORP.
Fig 6: Ignition Controls - Ignition Control Module