Air Temperature Sensor ( Ambient / Intake ): Description and Operation

Intake Air Temperature (IAT) Sensor






(1) Intake Air Temperature (IAT) Sensor
(2) Electrical Harness Connector

The intake air temperature (IAT) sensor is a thermistor (a resistor which changes value based on temperature) mounted in the intake manifold.

The low temperature produces a high resistance (100,000 ohms at -40�C/-40�F) while a high temperature causes a low resistance (70 ohms at 130�C/266�F).

The control module supplies a 5 volt signal to the sensor through a resistor in the control module and measures the voltage. The voltage will be high when the intake air is cold, and low when the air is hot. By measuring the voltage, the control module knows the intake air temperature.

The IAT signal is used by the control module in order to control the fuel.