Conditions For Setting DTC
WARNING: This page is about a different car, the 2003 Cadillac Seville and 2003 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
The PCM detects that the affected HO2S 1 voltage is 350-500 mV for more than 16 seconds, during a 120 second monitoring period.