Air Temperature Sensor ( Ambient / Intake ): Testing and Inspection

SCAN TOOL TESTING
A scan tool displays the temperature of the air entering the engine, which should be close to ambient air temperature when engine is cold, and rise as underhood temperature increases. If the engine has not been run for several hours (overnight), the ECT and IAT temperatures should be close to each other. A fault in the IAT sensor circuit should set either a DTC P0112 or DTC P0113. This DTC charts also contain a chart to check for sensor resistance values relative to temperature.