Intake Air Temperature 2 (IAT2) Sensor
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The IAT2 or manifold air temperature (MAT) sensor is a thermistor device. The electrical resistance of a thermistor decreases as the temperature increases, and resistance increases as the temperature decreases. The varying resistance affects the voltage drop across the sensor providing a signal corresponding to temperature.
The IAT2 sensor is located in the intake manifold. The sensor provides a manifold air temperature signal to the PCM.