Code Enable Criteria

• Engine run time is greater than 9.5 minutes.
• Engine speed is 650-900 RPM,
• Engine speed has been greater than 1200 RPM for 30 seconds after closed-loop.
• Short Term Fuel Trim (STFT) is 122-134.
• Calculated converter temperature is 707-1382°F (375-750°C).
• VSS at zero.
• Closed-loop status.
• MAP change is less than 6 kPa.
• No CMP, CKP, ECT, EGR, EVAP purge solenoid, 5-volt reverence, fuel trim, HO2S2, IAT, idle speed, MAP, misfire, O2S1 or TP DTCs have been set.

DTC sets when PCM has determined catalytic converter is no longer efficient by using the O2S1 and HO2S2 data.

DTC diagnostic is sampled once at idle once criteria has been met. If that test fails, PCM will take more samples during current ignition cycle, or may take more samples over several ignition cycles. Extra samples are to ensure converter has truly failed.