WARNING: This page is about a different car, the 2009 GMC Canyon and 2009 Chevrolet Colorado. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Power, Ground, Serial Data, and Controlled/Monitored Subsystem References
Courtesy of GENERAL MOTORS CORP.
Fig 2: Theft, Horn, Mirror, Power Moding, Brake and Wiper/Washer System References
Courtesy of GENERAL MOTORS CORP.
Fig 3: Interior Lights and Interior Lights Dimming References