Condition 1

WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0201, P0202, P0203, P0204, P0205, P0206 P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0273, P0274, P0276, P0277, P2146, P2149, P2152, P2155, P216A, or P216D is not set.
The ignition voltage is greater than 10 volts.
The engine is operating.
The air flow into the engine is greater than 10 grams.
The HO2S 1 heater duty cycle is greater than 90 percent for greater than 5 seconds.
DTC P0131 and P0151 run continuously once the conditions above exist for greater than 30 seconds.