Escort ZX2 L4-2.0L DOHC VIN 3 (2000)
Voltage that is dropped across a fixed resistor in a series with the sensor resistor determines the voltage signal at the PCM. This voltage signal is equal to
the reference voltage minus the voltage drop across the fixed resistor.
The IAT provides air temperature information to the PCM. The PCM uses the air temperature information as a correction factor in the calculation of
fuel, spark and MAF.
The IAT sensor provides a quicker temperature change response time than the ECT sensor.
Supercharged 5.4L Lightning vehicles use (2) IAT sensors. Both sensors operate as described above. However, one is located before the supercharger at
the air cleaner for standard OBD II/cold weather input, while a second sensor (IAT2) is located after the supercharger in the intake manifold. The IAT2
sensor located after the supercharger provides air temperature information to the PCM to control border-line spark and to help determine intercooler
efficiency.
