When Monitored
This diagnostic runs once per ignition cycle when the following conditions are met:
- Shortly after an initial engine start.
- The difference between the coolant temperature and ambient air temperature is greater than 15°C (27°F) at initial engine start.
- The engine coolant temperature recorded at the last engine shut down was above 83°C (181.4°F).
- If the previous engine shut down temperature was not above this value, the shut down diagnostic will not be performed during this ignition cycle.
- There was a minimum of 10°C (18°F) temperature drop during the last ignition off.
- If the above monitoring conditions are met, the PCM uses the engine coolant temperature drop to calculate a maximum ignition off time threshold.