P0113
PowertrainIntake Air Temperature Sensor 1 Circuit High Input
Your intake air temperature sensor is reporting a voltage that's higher than the ECU expects to see. In practice that nearly always means the sensor circuit is open, either disconnected, broken, or the sensor itself has gone.
ⓘ Information only. This page provides general educational information about fault code P0113. We do not assess the urgency or safety implications of any specific fault. That requires in-person diagnosis by a qualified mechanic. Full terms.
Recommended next steps
Whether a fault is urgent, drivable, or routine depends entirely on the cause on a specific vehicle, and that can only be determined by a qualified mechanic with diagnostic equipment. If a warning light is illuminated, the most reliable next step is professional diagnosis.
What does P0113 mean?
P0113 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Intake Air Temperature Sensor 1 Circuit High Input.
This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms commonly associated with this code
Symptoms that drivers often report alongside this code. Not all may apply to every case:
- • Engine warning light, often the only obvious sign
- • Slightly harder cold-starting on some engines
- • Marginally worse fuel economy until corrected
- • Occasional rough running on warm-up, less common
Possible causes
Causes commonly associated with P0113, listed in approximate order of typical investigation. The actual cause on a specific vehicle can only be confirmed by professional diagnosis.
- 1. Connector at the sensor unplugged, loose, or showing green corrosion on the pins (look here first, it's by far the most common cause)
- 2. Damaged signal or ground wire between the sensor and the ECU
- 3. The IAT sensor itself failed open-circuit
- 4. On engines where the IAT is built into the MAF sensor housing, a failed MAF
- 5. Rare: an issue with the ECU's 5V reference supply
How mechanics typically diagnose
A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training.
- 1. Pull the sensor connector and inspect it. Bent pins, water ingress, or corrosion will solve a lot of P0113s on the spot
- 2. Read live data with a code reader. An open-circuit fault almost always shows up as a -40°C reading
- 3. Resistance-test the sensor at a known temperature against the manufacturer's spec (a multimeter and a kettle is enough)
- 4. If the sensor is healthy, check continuity of the signal and ground wires back to the ECU before condemning anything else
Common questions about P0113
What temperature does the ECU think it's seeing? +
An open circuit usually shows -40°C in live data. The ECU's pull-up resistor takes the signal voltage to maximum, which the lookup table reads as the lowest possible temperature. P0113 is the high-voltage version of that fault.
Why is the air filter mentioned in some guides? +
It rarely is the cause. P0113 is an electrical fault, not an airflow fault. Replacing a dirty filter is sensible maintenance but it won't clear this code if the sensor or wiring is the issue.
How urgent is this one? +
Usually not very. Most engines will run on a default IAT value while the code is active. If the warning light is the only symptom and the car drives normally, fixing it within the next service interval is fine. Always confirm with a mechanic if in doubt.
Information only, not professional advice
The information on this page is provided for general guidance and educational purposes only. It is not a substitute for diagnosis or repair advice from a qualified mechanic. Always verify any fault before paying for repairs. carfaultcodes.co.uk accepts no liability for decisions made based on this information. Full terms →