WARNING: This page is about a different car, the 2008 GMC Yukon and 2008 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Power, Ground and Data Communication
Courtesy of GENERAL MOTORS CORP.
Fig 2: Battery Modules and Drive Motor Battery High Voltage Manual Disconnect Lever
Courtesy of GENERAL MOTORS CORP.
Fig 3: Main Power Contactors
Courtesy of GENERAL MOTORS CORP.
Fig 4: High Voltage Interlock Circuit (HVIC), Contactor Control Circuit