WARNING: This page is about a different car, the 2003 Buick Regal and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Power Door Locks Inoperative Diagnostic Procedure (Steps 1-13)
Courtesy of GENERAL MOTORS CORP.
Fig 2: Power Door Locks Inoperative Diagnostic Procedure (Steps 14-23)