WARNING: This page is about a different car, the 2010 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Radio Power, Ground, DLC and Audio Communications
Courtesy of GENERAL MOTORS CORP.
Fig 2: Speakers (UX8)
Courtesy of GENERAL MOTORS CORP.
Fig 3: Speakers (UY5) (1 of 3)
Courtesy of GENERAL MOTORS CORP.
Fig 4: Speakers (UY5) (2 of 3)
Courtesy of GENERAL MOTORS CORP.
Fig 5: Speakers (UY5) (3 of 3)
Courtesy of GENERAL MOTORS CORP.
Fig 6: Radio Antennas, Audio/Video Adapter
Courtesy of GENERAL MOTORS CORP.
Fig 7: Digital Radio Receiver (U2K)
Courtesy of GENERAL MOTORS CORP.
Fig 8: Traffic Information Receiver Module (VICS) - Japan Only