Code Enable Criteria

PCM will run diagnostic for this DTC under the following conditions:

• No active MAF, TP, IAT, MAP, AIR, injector circuit, EVAP, fuel trim or HO2S heater DTCs SET.
• Mass airflow is 10-30 grams per second.
• ECT is more than 122°F (50°C).
• Engine speed is 1000-3000 RPM.
• Above conditions present for a 100 second monitoring period after closed loop.
• System voltage is 9-18 volts.
• Air pump commanded off.

DTC will set when HO2S 1 transition time ratio is less than 0.3 or greater than 35. Conditions must be present for a 100 second monitoring period.