GM Service Manual Online
For 1990-2009 cars only

System

DTCs Required to Set System Status to YES

Catalyst

DTC P0420 Catalyst System Low Efficiency

Exhaust Gas Recirculation (EGR)

DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient

Evaporative Emission (EVAP)

DTC P0442 Evaporative Emission (EVAP) System Small Leak Detected

DTC P0446 Evaporative Emission (EVAP) Vent System Performance

DTC P0455 Evaporative Emission (EVAP) System Large Leak Detected

DTC P0496 Evaporative Emission (EVAP) System Flow During Non-Purge

Oxygen Sensor

DTC P0133 HO2S/O2S Slow Response Sensor 1

DTC P0140 HO2S Circuit Insufficient Activity Sensor 2

DTC P1133 HO2S Insufficient Switching Sensor 1

DTC P1134 HO2S Transition Time Ratio Sensor 1

DTC P2A01 HO2S Circuit Bank 1 Sensor 2

Oxygen Sensor Heater

DTC P0135 HO2S Heater Performance Sensor 1

DTC P0141 HO2S Heater Performance Sensor 2