Conditions For Setting DTC
WARNING: This page is about a different car, the 2003 GMC Sonoma and 2003 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.
PCM detects that the HO2S 2 parameter remains within 150 mV of the start-up voltage for a pre-determined amount of time based on ECT and air flow.