P0110 - IAT SENSOR 1 CIRCUIT MALFUNCTION

The IAT sensor (Intake Air Temperature) measures the temperature of the air when it detects the resistance in the air. This is generally located in the part of the intake air duct network, but depending on the vehicle it can also be in the intake manifold.

This sensor has two cables supplied by the Powertrain Control Module (PCM), one is a reference signal that is 5 volts, while the other cable is the one that provides the ground.

When the air passes through the IAT sensor (input air temperature sensor) the resistance changes. It should be mentioned that the change in resistance affects the 5 volts that are supplied to the sensor. If the air is cold, the resistance increases thus giving a higher voltage, on the other hand, the resistance drops if the air is warmer while obtaining a lower voltage. In the event that the PCM (Power Train Control Module) detects a voltage that is outside the sensor’s normal function range, the DTC code P0110 OBD2 is set.

• The Check Engine light comes on.
• Malfunction when accelerating.
• In idle it is unstable.

The reasons that can lead to the establishment of fault code P0110 OBD II are:

• The Intake Air Temperature (IAT) Sensor may be out of the air flow.
• The electrical connection of the IAT sensor could be defective due to cables or connectors in poor condition.
• The supply circuit or earth circuit of the Intake Air Temperature sensor may be short.
• IAT sensor defective.

Before the diagnostic code P0110 you must do the following:

• With a scanner you should see the live data and verify if 5 volts of input are present for the Intake Air Temperature (IAT) sensor. In case the input voltage of the IAT sensor to the PCM is not within the parameter already established, it is indicative that it is defective, so you must change it.
• Check the cables and connectors that lead to the Input Air Temperature Sensor (IAT), make sure they are in good condition. Also, there is a good connection. Repair or change as necessary. A good reading of this sensor is 5 volts which increase as the engine temperature rises.
• If after doing all the previous tests the code keeps appearing, you must change the IAT sensor.
• Change the Multiple Absolute Pressure Sensor (MAP).