WARNING: This page is about a different car, the 2008 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Radio and Amplifier Power, Ground, and Communication UQA
Courtesy of GENERAL MOTORS CORP.
Fig 2: Radio and Amplifier Power, Ground, and Communication UQS -U42
Courtesy of GENERAL MOTORS CORP.
Fig 3: Radio, Amplifier, Power, Ground, and Communication UQS +U42