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

Intake Air Temperature Sensor Circuit.:






PURPOSE
The Intake Air Temperature (IAT) sensor determines intake air temperature. The intake air temperature along with manifold pressure and engine RPM are utilized by the PCM to determine base air fuel mixture delivered by the fuel injection system.

OPERATION
Low intake air temperature produces a high resistance, while high intake air temperature produces a low resistance. The PCM supplies a 5.0 volt signal to the sensor through a resistor and measures the voltage. By measuring the voltage, the PCM can determine Intake Air Temperature.

LOCATION
The Intake Air Temperature sensor (IAT) is a thermistor mounted in the air intake duct.