Air Temperature Sensor ( Ambient / Intake ): Description and Operation

Intake Air Temperature Sensor:

The Intake Air Temperature sensor (IAT), mounted on the air cleaner, is a thermistor with a negative temperature coefficient. This means as temperature increases, resistance decreases. Low intake air temperature produces a high resistance, while high intake air temperature produces a low resistance. The PCM provides a 5 volt reference to the sensor and measures the voltage drop in the circuit. Each voltage value corresponds to a discrete resistance of the sensor. From this information, the control module calculates the temperature of the intake air.