Conditions For Setting DTC
WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
PCM detects that the HO2S 1 parameter is more than 700 mV and HO2S 2 parameter is less than 399 mV for 9.5 seconds.