WARNING: This page is about a different car, the 2004 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Dash Integration Module (DIM) Power, Ground And Serial Data
Courtesy of GENERAL MOTORS CORP.
Fig 2: Ignition Switch
Courtesy of GENERAL MOTORS CORP.
Fig 3: DIM Inputs And Outputs - 1 Of 3
Courtesy of GENERAL MOTORS CORP.
Fig 4: DIM Inputs And Outputs - 2 Of 3
Courtesy of GENERAL MOTORS CORP.
Fig 5: DIM Inputs And Outputs - 3 Of 3
Courtesy of GENERAL MOTORS CORP.
Fig 6: Rear Integration Module (RIM) Power, Ground And Serial Data