WARNING: This page is about a different car, the 2004 Saturn L300. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: EBCM Power, Ground, Serial Data & Switches Wiring Schematic - 2.2L
Courtesy of GENERAL MOTORS CORP.
Fig 2: EBCM Power, Ground, Serial Data & Switches Wiring Schematic - 3.0L