Bad intake air temperature sensor (both sources). IAT sensor shifted out of the airflow (OBD-Codes.com). Open or short to ground in the IAT signal wire, or an open in its ground wire (OBD-Codes.com). Poor connection at the sensor, such as backed-out terminals or a broken connector lock (OBD-Codes.com), or corroded wiring and connections (RepairPal). Dirty air filter (RepairPal). Faulty mass air flow sensor (RepairPal). Failed PCM (OBD-Codes.com).

Reseat or reposition a dislodged IAT sensor. Repair damaged wiring or a poor connection in the IAT circuit. Replace the air filter if it is dirty. Replace the IAT sensor if its resistance is out of spec. Have the MAF sensor or PCM checked only after the sensor and wiring test good.

P0110🔧 Engine sensors / air intakeDrive with caution, fix soon

P0110: Intake Air Temperature Sensor Circuit (Meaning, Causes, Fixes)

Q: What does P0110 mean?

P0110 means the engine computer (PCM) sees a problem in the intake air temperature (IAT) sensor circuit. Common causes are a bad IAT sensor, a sensor knocked out of the airflow, damaged or corroded wiring and connectors, and, less often, a failed PCM. RepairPal also lists a dirty air filter and a faulty mass air flow sensor. The intake air temperature (IAT) sensor is a thermistor, a sensor whose resistance changes with temperature. It usually sits in the intake air ductwork, though on some engines it is in the intake manifold. It is usually a two-wire sensor: the PCM supplies a 5 volt reference that doubles as the signal wire, plus a ground. Colder air means higher resistance and a higher signal voltage, and warmer air means lower resistance and a lower voltage (OBD-Codes.com). The PCM uses the reading to help set the air/fuel ratio, ignition timing and emissions controls (RepairPal). P0110 is a generic OBD-II code. The sources describe when it sets a little differently: OBD-Codes.com says it sets when the PCM sees a voltage outside the sensor's normal operating range, while RepairPal says it sets on inconsistent or erratic voltage from the sensor circuit. P0112 (circuit low) and P0113 (circuit high) are the more specific versions of the same circuit fault, and P0111 is the range/performance code.

Q: Can I keep driving with P0110?

Drive with caution, fix soon. Get this checked within a reasonable time. RepairPal rates P0110 'Moderate', meaning it may not threaten safety right away but should be diagnosed soon. OBD-Codes.com says there may be no symptoms beyond the check engine light, though drivability complaints are possible. If the engine hesitates badly or is hard to start, have it looked at sooner.

Reviewed 2026-10-24 · Based on 2 cited source(s)

What P0110 means

The intake air temperature (IAT) sensor is a thermistor, a sensor whose resistance changes with temperature. It usually sits in the intake air ductwork, though on some engines it is in the intake manifold. It is usually a two-wire sensor: the PCM supplies a 5 volt reference that doubles as the signal wire, plus a ground. Colder air means higher resistance and a higher signal voltage, and warmer air means lower resistance and a lower voltage (OBD-Codes.com). The PCM uses the reading to help set the air/fuel ratio, ignition timing and emissions controls (RepairPal). P0110 is a generic OBD-II code. The sources describe when it sets a little differently: OBD-Codes.com says it sets when the PCM sees a voltage outside the sensor's normal operating range, while RepairPal says it sets on inconsistent or erratic voltage from the sensor circuit. P0112 (circuit low) and P0113 (circuit high) are the more specific versions of the same circuit fault, and P0111 is the range/performance code.

Severity: can I keep driving?

Drive with caution, fix soon

Get this checked within a reasonable time. RepairPal rates P0110 'Moderate', meaning it may not threaten safety right away but should be diagnosed soon. OBD-Codes.com says there may be no symptoms beyond the check engine light, though drivability complaints are possible. If the engine hesitates badly or is hard to start, have it looked at sooner.

Common symptoms

Check engine light on
Often no other symptoms (OBD-Codes.com)
Hard starting or poor fuel economy in some cases (RepairPal)
Poor performance or hesitation on acceleration (RepairPal)

Likely causes

Roughly most to least common, based on the sources below. Your vehicle may differ.

Bad intake air temperature sensor (both sources)
IAT sensor shifted out of the airflow (OBD-Codes.com)
Open or short to ground in the IAT signal wire, or an open in its ground wire (OBD-Codes.com)
Poor connection at the sensor, such as backed-out terminals or a broken connector lock (OBD-Codes.com), or corroded wiring and connections (RepairPal)
Dirty air filter (RepairPal)
Faulty mass air flow sensor (RepairPal)
Failed PCM (OBD-Codes.com)

Diagnostic steps you can do

⚠ Before you start

Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.

Make sure the IAT sensor is in place in the intake duct and hasn't been knocked loose, and check its connector for backed-out terminals, broken locks or corrosion.
Check the air filter; RepairPal says a dirty filter is a common real cause when the sensor gets replaced for nothing.
With a scan tool and the key on, engine off (and the engine cold), compare the IAT reading to the coolant temperature reading. They should be close. A reading stuck at an extreme like -40 or 300 degrees points to a circuit or sensor fault (OBD-Codes.com).
Unplug the sensor and measure its resistance across the two terminals, comparing it to the repair manual spec. Infinite resistance means the sensor is bad (OBD-Codes.com).
At the unplugged connector, check for a steady 5 volt reference and a good ground (both sources).

Typical fixes

Reseat or reposition a dislodged IAT sensor
Repair damaged wiring or a poor connection in the IAT circuit
Replace the air filter if it is dirty
Replace the IAT sensor if its resistance is out of spec
Have the MAF sensor or PCM checked only after the sensor and wiring test good

Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.

🛠 When to call a pro

The sensor has 5 volts and a good ground but the reading still doesn't change when you unplug or jumper it; OBD-Codes.com says that can mean a wiring open or a PCM problem
You need the make-specific resistance spec or wiring diagram
RepairPal suggests shops recreate the code on a test drive while watching the IAT on a live data scan tool
Other sensor codes such as MAF or coolant temperature codes also appear

Where to buy

Plain search links. Always match parts to your exact year, make, model and engine.

OBD2 scanners on Amazon Parts at Advance Auto Parts catalog at RockAuto

FAQs

What's the difference between P0110, P0112 and P0113?

All three are intake air temperature sensor 1 circuit codes. P0110 is the general circuit malfunction code, P0112 means the circuit reads low and P0113 means it reads high.

Can a dirty air filter cause P0110?

RepairPal lists a dirty air filter as a common cause and says the IAT sensor often gets replaced when the filter was the real problem, so it is worth checking first.

Is it safe to drive with P0110?

RepairPal rates it 'Moderate'. Often the only symptom is the check engine light, but get it diagnosed soon, since the engine computer uses the reading to set fuel and timing.

How much does it cost to fix P0110?

Neither source gives a repair cost. It can range from reseating a connector or replacing an air filter to a new IAT or MAF sensor, so get a diagnosis and a written estimate first.

Sources

Last reviewed 2026-10-24. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.