P0113 Code: Intake Air Temperature Sensor 1 Circuit High
The intake air temperature signal is stuck at maximum voltage, which usually means an open circuit.
At a glance
Severity: Low
- Meaning
- Intake Air Temperature Sensor 1 Circuit High
- System
- Fuel & Air Metering · Powertrain
- Safe to drive?
- Yes, short term
- Typical repair cost
- $0–$450
- DIY difficulty
- Easy
The intake air temperature (IAT) sensor is a thermistor whose resistance drops as air gets warmer. The PCM sends it a 5-volt reference and reads the voltage that comes back: cold air means high voltage, warm air means low voltage. P0113 sets when that voltage sits at or near the full 5 volts, which the PCM reads as impossibly cold air, typically showing -40°F in live data. That almost always means the circuit is open somewhere: an unplugged connector, a broken wire or a sensor that has failed open. On many vehicles the IAT is built into the MAF sensor housing.
Can I keep driving? Safe to drive. The PCM substitutes a default air temperature, so you may only notice slightly worse gas mileage or a rougher cold start, but the check engine light will fail an emissions test.
Try this first – 5-minute fix
- Check the plug first If the code appeared right after an air filter change or any work near the intake, reseat the MAF or IAT connector until the locking tab clicks.
- Look for -40°F Read intake air temperature with a scanner. A reading close to outside temperature after reseating the plug means the fault is fixed.
- Clear and confirm Clear the code, start the engine and drive a few miles. If P0113 doesn't return, the loose connector was the whole problem.
How to read P0113
- P Powertrain
- 0 Generic (SAE)
- 1 Fuel & air metering
- 13 Specific fault
Symptoms
- Check engine light on
- Live data shows intake air temperature around -40°F regardless of weather
- Slightly lower gas mileage
- Harder or rougher starts in hot weather on some vehicles
- Often no noticeable drivability change at all
Possible causes
Ranked by how often each cause is behind this code (editorial estimate).
- Sensor or MAF connector unplugged or not fully latched, often after an air filter change or intake work
- Open signal or sensor-ground wire (chafed harness, rodent damage, broken at the connector)
- IAT sensor failed open internally
- Corroded, bent or spread terminals in the connector
- Shared sensor ground fault or PCM problem
Diagnosis step by step
Compare IAT with outside temperature
After the car has sat overnight, IAT and coolant temperature in live data should both be close to the outside air temperature. If IAT reads -40°F while coolant reads normal, the IAT circuit is open.
Tools: OBD-II scanner
Inspect the connector and harness
Locate the IAT: in the MAF housing, the air intake tube or the airbox. Check that the plug is fully seated, the terminals aren't green or pushed back, and the wires aren't stretched or chewed.
Tools: Flashlight
Do a jumper test at the connector
Unplug the sensor and briefly connect the signal and sensor-ground terminals on the harness side with a fused jumper while watching IAT in live data. If the reading jumps to a very hot value, the wiring and PCM are fine and the sensor is bad; if it stays at -40°F, the fault is in the wiring.
Tools: OBD-II scanner, Multimeter
Measure the sensor resistance
On a standalone IAT, measure across the two sensor pins: expect a few thousand ohms at room temperature, dropping steadily as you warm the tip with a hair dryer. An infinite reading means the thermistor is open.
Tools: Multimeter
Check the 5-volt reference and ground
With the key on and the sensor unplugged, the signal wire should show about 5 volts and the ground wire should show near zero volts relative to battery negative. If the coolant temperature sensor also reads wrong, look for a shared sensor-ground problem.
Tools: Multimeter
Where the parts are
- 1Ignition coil
- 2Spark plug
- 3Fuel injector
- 4Camshaft sensor
- 5Crankshaft sensor
- 6Engine computer (ECM)
- 7Intake manifold
Repair options & costs
| Repair | DIY? | Estimated cost |
|---|---|---|
| Reseat or secure loose connector | Yes | $0 |
| Clean and repair connector terminals | Yes | $10–$90 |
| Replace standalone IAT sensor | Yes | $25–$120 |
| Replace MAF sensor with integrated IAT | Yes | $150–$450 |
| Repair open wiring in the harness | No | $100–$300 |
Rough US estimates for parts and labor; shop rates vary by region. Not a quote.
Notes by brand
Field data
| Nissan | 3 | Rogue, Kicks | |
|---|---|---|---|
| Dodge | 2 | Durango, Journey | |
| Toyota | 2 | Corolla, Prius |
Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.
Emissions / smog test impact
Will fail
Although the car may drive normally, the check engine light alone fails an OBD-II smog or emissions inspection. Once the circuit is fixed, clear the code and allow a few days of normal driving for the readiness monitors to set.
Frequently asked questions
My scanner shows -40°F intake air temperature. Is that the sensor?
Not necessarily. -40°F is simply the reading the PCM shows when it sees an open circuit, so an unplugged connector or broken wire looks exactly the same as a dead sensor. The jumper test at the connector tells you which it is.
Why do I have P0113 and P0102 at the same time?
On vehicles where the IAT is built into the MAF sensor, both share one connector. When that plug is loose or unplugged, the PCM loses both signals at once and sets a MAF low input code alongside P0113.
Do I need a whole new MAF sensor if the IAT is built into it?
On most vehicles with an integrated IAT, yes, because the thermistor isn't sold separately. Confirm the wiring is good with the jumper test before spending money on a MAF sensor.
Can P0113 damage my engine?
No, it's one of the milder codes. The PCM substitutes a default value, so fueling and spark timing are only slightly less accurate. The main consequences are a small loss in fuel economy and a failed emissions test.