Intake Air Temperature Switch: Description and Operation

Intake Air Temperature (IAT) sensor
The Intake Air Temperature (IAT) sensor is a thermistor device mounted inside the MAF sensor. It provides an input signal to the ECM proportional to the temperature of air passing through the inlet duct into the engine. A DTC is recorded if the voltage input signal from the sensor to the ECM is outside pre-defined thresholds at the High or Low end of the scale.