Monitor Description
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The ECM monitors the difference between the engine coolant temperature and the intake air temperature (for mass air flow meter sub-assembly) when the engine is started cold to accurately detect the engine temperature conditions. The monitor runs when the engine is started after 7 hours or more have elapsed since the engine was stopped (engine switch turned off) on the previous trip. If the difference between the engine coolant temperature and the intake air temperature on a cold start exceeds 25°C (45°F), the ECM interprets this as a malfunction in the engine coolant temperature sensor circuit and intake air temperature sensor circuit, and stores this DTC.