Outline Of Diagnosis
Detect the malfunction of the intake air temperature sensor (integrated with air flow sensor) output properties. Using the following two diagnoses, judge as NG when either is NG.
- Diagnosis 1 (correlation diagnosis): After the engine starts after the specified period of soaking time has elapsed, diagnose by correlation between intake air temperature sensor value, engine coolant temperature sensor value and ambient temperature sensor value. Judge as NG when the differences are both above the specified value by comparing between intake air temperature and engine coolant temperature, intake air temperature and ambient air temperature.
- Diagnosis 2 (stuck diagnosis): Judge as NG when intake air temperature does not change under the driving condition where it should change, considering engine condition.