The Intake Air Temperature (IAT) sensor is a variable resistor which changes in response to intake air temperature. The resistance decreases as the surrounding air temperature increases. This temperature signal is sent to the Engine Control Module (ECM). The IAT sensor is located at the intake port or exit port of the air cleaner or in the intake manifold.
With ignition OFF , disconnect the IAT sensor. Measure the resistance across the sensor connector terminals. If the reading for a given temperature is about that shown in the table, the IAT sensor is okay.