Circuit Description

The DTC P0110 Intake Air Temperature (IAT) sensor circuit diagnostic detects an out of range sensor signal. IAT sensor is a thermistor that is an integral part of the Mass Air Flow (MAF) sensor. Electrical resistance of IAT sensor is high when the air temperature is cold, and resistance is low when air temperature is warm. IAT sensor is wired in series with a fixed resistor located in the Powertrain Control Module (PCM). PCM applies 5 volts to the IAT sensor. PCM monitors voltage across IAT sensor and converts voltage into a temperature reading. Voltage measured by PCM will be high when air temperature is cold, and low when air temperature is warm. See IAT RESISTANCE/SIGNAL VOLTAGE  table.