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

EGR

DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient

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 Slow Response Bank 1 Sensor 1

DTC P0140 HO2S Circuit Insufficient Activity Bank 1 Sensor 2

DTC P0133 HO2S Insufficient Switching Bank 1 Sensor 1

DTC P1133 HO2S Transition Time Ratio Bank 1 Sensor 1

DTC P2A01 HO2S Circuit Closed Loop (CL) Performance Bank 1 Sensor 2

Oxygen Sensor Heater

DTC P0135 HO2S Heater Performance Bank 1 Sensor 1

DTC P0141 HO2S Circuit Low Voltage Bank 1 Sensor 2