Diagnostic Aids
WARNING: This page is about a different car, the 2001 GMC Savana, 2001 Chevrolet RV Cutaway, 2001 Chevrolet Cutaway, and 2001 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.
An oxygen supply inside HO2S is necessary for proper operation. HO2S wires provides supply of oxygen. Inspect HO2S wires and connections for breaks or contamination.