Code 24, Intake Air Temp Sensor CKT, Open Or Shorted CKT: Notes

IAT sensor uses a thermistor to control signal voltage at ECM. ECM applies 4-6 volts to the sensor. When air is cold, thermistor resistance is high, thus ECM senses high signal voltage. If air is warm, sensor resistance is low, thus ECM senses low signal voltage.

1. Verifies 4-5 volts are present at IAT sensor connector.
2. Checks ground side of IAT sensor circuit.
3. Determines if problem is caused by an open circuit or ECM.
4. Determines if Yellow/Black wire is open or if ECM is faulty.