Prizm L4-108 1.8L DOHC VIN 8 MFI (1995)
Intake Air Temperature (IAT) Sensor: Description and Operation
DESCRIPTION
The Intake Air Temperature (IAT) sensor is mounted in the air cleaner assembly. This sensor measures the temperature of the air entering the
intake manifold and provides this information to the PCM for use in calculating air density. The PCM uses IAT, MAP and engine speed to
calculate the quantity of air flowing into the engine.
OPERATION
The IAT sensor is a thermistor (a resistor whose resistance changes as a function of temperature). When the temperature is low, the resistance is
high. The resistance decreases as temperature increases. The IAT sensor is a "two-wire" sensor with a reference or signal voltage and a ground
coming from the PCM.
SENSOR CIRCUIT FAILURE
A failure in the IAT sensor circuit should set a DTC 24 Intake Air Temperature Sensor Circuit.
