Perform SIR System Diagnostic Check
WARNING: This page is about a different car, the 2002 Buick Regal and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
SIR diagnostic system check should always be starting point for any SIR diagnostics. It checks for proper AIR BAG warning light operation and SIR trouble codes using scan tool. See SIR DIAGNOSTIC SYSTEM CHECK under DIAGNOSTICS.