Intake Air Temperature (IAT) Sensor
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2004 Ford RV Cutaway, 2004 Ford Pickup, 2004 Ford F550 Super Duty, 2004 Ford F450 Super Duty, and 2004 Ford Excursion. However, it is still accessible from the selected car via links, so may be relevant.
The intake air temperature (IAT) 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 6.0L diesel utilizes two IAT sensors. The IAT sensor is integrated into the mass air flow (MAF) sensor. The PCM uses the IAT signal to control timing and fuel rate during cold starts and provide an input to the cold idle kicker.