Fuel and air

P0110 — Intake Air Temperature (IAT) Sensor Circuit Malfunction

Severity: low Safe to drive

What P0110 means

The engine control module received an IAT sensor signal that is out of range or missing. The sensor is normally a thermistor whose resistance changes with temperature, and the module reads its voltage to estimate air density. It uses that to adjust fuel delivery and ignition timing. With a bad signal, the air-fuel calculation becomes less accurate.

Symptoms

  • Check Engine light on
  • Rough idle
  • Hesitation when accelerating
  • Reduced fuel economy
  • Loss of power
  • Hard starting in hot or cold conditions

Possible causes

  1. Failed IAT sensor
  2. Corroded or damaged sensor connector
  3. Open circuit or short to ground or power in the wiring
  4. Failed combined MAF/IAT sensor where the IAT is built into the airflow meter
  5. Loose or poor terminal contact
  6. Rarely, a faulty input circuit in the control module

How to diagnose

  1. Read the codes and freeze frame data and note whether the fault is a low or high signal
  2. Inspect the sensor connector and harness for corrosion, chafing, moisture and a loose fit
  3. With a scan tool, compare IAT reading to ambient temperature on a cold engine; they should be close
  4. Unplug the sensor: if the reading goes to an extreme and changes to the opposite when the terminals are jumpered, the circuit is fine and the sensor is suspect
  5. Measure the sensor resistance and compare with the manufacturer's chart for that temperature
  6. Check for 5 V reference and a good ground at the connector
  7. Test the wires to the control module for opens and shorts
  8. If all else checks out, evaluate the module's input circuit

Common fixes

  • Replace the IAT sensor
  • Repair the wiring or replace the connector
  • Clean the terminals and secure the connector
  • Replace the MAF sensor if the IAT is integrated into it
  • In rare cases, repair or replace the control module

P0110 on different brands

Ford · manuals
On Ford, P0110:16 is read as Intake Air Temperature Sensor 1 Circuit Low (Bank 1), meaning the circuit voltage is below the expected threshold.

Questions and answers

Can I drive with a P0110 code?

Usually yes, for short trips. The module uses a default value, but the mixture may be off and fuel use higher. Have it checked soon.

What most often causes P0110?

Most often it's the sensor itself or poor contact in its connector. Inspect the connector and wiring first, then test the sensor.

Do I need to replace the MAF sensor for P0110?

Only if the IAT is built into the airflow meter and testing shows it has failed. If the IAT sensor is separate, the MAF doesn't need replacing.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.