G 1500 1/2 Ton Van V8-5.7L VIN R (1996)
Intake Air Temperature (IAT) Sensor: Description and Operation
Intake Air Temperature (IAT) Sensor
PURPOSE
The Intake Air Temperature (IAT) sensor is a thermistor which changes value based on the temperature of air entering the engine.
OPERATION
Low temperature produces a high resistance 100,000 ohms at -40° (-40°F). A high temperature causes low resistance 70 ohms at 130°C (266°F).
The VCM supplies a 5.0 volt signal to the sensor through a resistor in the VCM and measures the voltage. The voltage will be high when the
incoming air is cold, and low when the air is hot. By measuring the voltage, the VCM calculates the incoming air temperature. The IAT sensor
signal is used to adjust spark timing according to incoming air density.
