Conditions For Setting DTC
WARNING: This page is about a different car, the 2003 Pontiac Aztek and 2003 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
PCM detects that the HO2S 1 voltage switched from rich-to-lean fewer than 20 times within a 100 ms monitoring period.
PCM detects that the HO2S 1 voltage switched from lean-to-rich fewer than 20 times within a 100 ms monitoring period.