DTC P0112: Intake Air Temperature Sensor 1 Circuit Low Input: General Description

The IATS (Intake Air Temperature Sensor) measures the temperature of engine intake air. The IATS (Intake Air Temperature Sensor) is a thermistor (a variable resistor that changes along with outside air temperature) in series with a fixed resistor in the PCM. The PCM applies 5V to the IATS. The PCM monitors the voltage across the IATS and converts it into a temperature reading. When the outside air temperature is cold the IATS resistance is high, and when the outside air temperature is warm the IATS resistance is low. Therefore, when the air temperature is cold the PCM will receive a high voltage input, and when the air temperature is warm the PCM will receive a low voltage input. The signal from IATS is used for injection duration correction, ignition timing correction and idle speed correction (Air-density correction).