P0113low severityGenerally driveableP0113 Code: Intake Air Temperature Sensor Circuit High Input
Written in plain English and reviewed by the eli5cars editorial team · Last reviewed June 2026
What it means in plain English
Your engine's intake air temperature (IAT) sensor measures how hot or cold the air is that's entering the engine. The ECM uses this to adjust the fuel mixture — cold air is denser and carries more oxygen, so the engine needs a bit more fuel; hot air needs less. The IAT sensor works like a thermistor: its electrical resistance changes with temperature, which changes the voltage the ECM sees. P0113 means the ECM is seeing a very high voltage on the IAT signal wire — which corresponds to an impossibly cold reading (well below freezing, even on a summer day). This usually means the sensor's circuit is open: a broken wire, failed sensor, or corroded connector. The ECM may substitute a fixed value and keep running, but fuel trim accuracy suffers.
Most likely causes — ranked
#1 Open circuit in the IAT sensor or its wiring (most common cause of high-voltage code)
most likelyFix: An open circuit lets the signal wire float to the reference voltage (usually 5 V), which the ECM interprets as an extremely cold temperature. With the sensor unplugged, measure the resistance across the sensor terminals — a good IAT sensor reads roughly 2,000–3,000 ohms at room temperature (70°F). An open circuit (OL on the meter) means the sensor is bad. Also check the signal and ground wires in the harness for breaks or corrosion. Repair wiring first; if it checks out, replace the sensor.
#2 Failed or contaminated IAT sensor
likelyFix: IAT sensors fail internally over time, especially in dusty or oily intake environments. Many IAT sensors are integrated into the MAF sensor body and can only be replaced as an assembly. Others are standalone sensors clipped or threaded into the intake tract. Confirm whether your IAT is standalone or built into the MAF before ordering parts. If standalone, a replacement IAT sensor is inexpensive.
#3 Corroded or loose IAT sensor connector
likelyFix: The IAT connector sits in the intake tract where condensation and oil vapor collect. Inspect the connector for green or white corrosion on the pins. Disconnect it, clean the pins with electrical contact cleaner, apply dielectric grease, reconnect firmly, and clear the code. Many P0113 cases resolve with connector cleaning alone.
#4 High-resistance ground in the IAT sensor circuit
possibleFix: A poor ground connection elevates the signal voltage without a full open circuit. Locate the IAT sensor ground wire in the wiring diagram and check continuity from the sensor connector ground pin to the chassis ground point. High resistance (more than a few ohms) in the ground path will cause the ECM to read high voltage on the signal line. Clean or replace the ground connection.
Check engine light on? Get a free code scan
If your check engine light is on, most auto-parts stores (AutoZone, O'Reilly, Advance) will read the code for FREE — no purchase required, just walk in. Bring the code back here and look it up at eli5cars.com/obd2 for the plain-English explanation.
Note: a scan only helps when there's an active fault code. For purely mechanical symptoms (noises, vibrations, leaks), a scan may show nothing — the suspects listed above are your starting point.
Want to read the codes yourself?
First, the free option: AutoZone, O’Reilly, and Advance Auto Parts read your codes for free — no purchase needed. That’s the cheapest way to get the code to look up here. If you’d rather have your own so you can check anytime (and clear a code after a fix), the Veepeak OBDCheck BLE is an inexpensive, reliable plug-in reader that pairs with a free phone app and works on any car sold since 1996.
See the Veepeak OBD2 scanner on AmazonAffiliate link — we may earn a commission at no extra cost to you. Details.
Frequently asked questions
Can I drive with P0113?
Yes, the car will typically run with P0113. The ECM usually substitutes a default air temperature value and keeps running in a slightly degraded mode. You may notice slightly worse fuel economy or a minor rich condition, especially at startup. Fix it when convenient — it's not an emergency.
How do I know if the IAT is integrated into my MAF sensor?
Count the wires in your MAF sensor connector. A MAF sensor by itself typically has 4–5 wires. If your MAF connector has 5–6 wires, one pair is likely the IAT circuit. You can also look up your vehicle's wiring diagram — search your year/make/model plus 'MAF wiring diagram.' If the IAT is integrated, replacing just the MAF sensor resolves both MAF and IAT faults.
Will P0113 cause poor fuel economy?
Modestly. The ECM may think the intake air is colder than it is, causing it to slightly over-fuel. The effect is usually small — a few percent — because modern ECMs use fallback values that are reasonably close to reality. Fixing it restores full accuracy.
How can I get a free scan to confirm P0113?
AutoZone, O'Reilly, and Advance Auto Parts scan for free. If you want to check live IAT sensor readings (temperature values and voltage), you need a scanner with live data — inexpensive Bluetooth OBD2 adapters with a free phone app can show this data.