Sable V6-183 3.0L DOHC VIN S MFI (1997)
Intake Air Temperature Sensor: Description and Operation
Typical Intake Air Temperature (IAT) Sensors
PURPOSE
The Intake Air Temperature (IAT) sensor measures varying air charge temperature information. This information is supplied to the Powertrain
Control Module (PCM). The IAT signal is used by the PCM as a correction factor in fuel, spark, and MAF. The IAT sensor provides quicker
temperature change response time than the Engine Coolant Temperature Sensor (ECT).
OPERATION
Variations in temperature affect the voltage drop across the sensor terminals, providing electrical signals to the PCM.
CONSTRUCTION
The IAT is a thermistor device in which resistance decreases as the temperature increases, and increases as the temperature decreases. Thermistor-type
sensors are considered passive sensors. A passive sensor is connected to a voltage divider network so that varying the resistance of the sensor causes a
variation in total current flow.
