DTC code page

P0113: Intake Air Temperature Sensor 1 Circuit High Input

Quick answer: The ECU sees the IAT signal pulled high, which usually makes the intake temperature look implausibly cold.

Drivers also search this fault as intake air temperature circuit high input, IAT high voltage, IAT sensor reads cold all the time.

Severity: medium Family: powertrain Related paths: 10
Meaning

What P0113 usually means

P0113 is the high-input side of the intake-air-temperature family. Because IAT sensors are usually thermistors, a high signal voltage usually means the ECU thinks the incoming air is much colder than reality. That can push the calibration toward richer fueling, altered load estimates, and cold-air assumptions that do not match what the engine is actually breathing. It is especially relevant on vehicles that feel heavy, rich, or unusually lazy after warm-up even though the code sounds minor.

Fast triage

Start here before chasing parts

  • Scan first: save freeze-frame and pending codes before clearing anything.
  • Confirm the complaint: compare the stored code with current drivability symptoms.
  • Use context: trims, live data, and related codes usually narrow the fault faster than guesswork.
  • Work simplest to hardest: leaks, connectors, maintenance items, and known patterns before expensive components.
Initial checks

What to check first

  • Read IAT on a cold engine and compare it with ambient to see whether the scan tool shows an impossible deep-cold value.
  • Physically inspect whether the sensor or MAF connector is partly unplugged, which is a classic P0113 cause.
  • Look for rich-running or poor-MPG symptoms that support the false-cold story.
Driving risk

Can you keep driving?

P0113 is usually not a stop-now code, but a false-cold intake reading can enrich the mixture long enough to hurt fuel economy, foul plugs, and create confusing secondary codes.

Moderate urgency: This code often allows short-term driving, but the right fix usually comes faster when you diagnose it early instead of waiting for more codes.
Likely causes

Common causes behind this code

  • Open circuit in the IAT signal or ground path
  • Sensor unplugged or connector terminals spread
  • Broken wire inside the harness near the airbox or MAF housing
  • Integrated MAF/IAT assembly fault causing a stuck-cold reading
  • High resistance in the connector or shared sensor ground

Cause phrases often tied to this code: open IAT circuit, sensor unplugged, broken signal wire, high resistance in connector, false cold intake reading.

Diagnostic order

Suggested workflow

  1. Compare scan-tool IAT with real ambient temperature after an overnight cold soak.
  2. Inspect the sensor connector for loose fit, backed-out pins, or broken wire strands near the plug.
  3. Check circuit continuity and verify the sensor can actually pull the signal lower as temperature changes.
  4. If the IAT is built into the MAF, inspect whether the full assembly is losing signal or only the temperature side.
  5. After repair, confirm the reading no longer sticks unrealistically cold and that rich-running behavior improves.
Avoid guesswork

Common mistakes

  • Replacing oxygen sensors because the car smells rich without noticing the intake temperature is lying to the ECU.
  • Ignoring a partly unplugged MAF or IAT connector after recent service or air-filter work.
  • Confusing a false-cold IAT story with a coolant-temperature problem without comparing both on a cold start.
Repair path

Practical fix guidance

  • Restore proper circuit continuity and connector grip before replacing parts blindly.
  • If the sensor is integrated into the MAF, replace the assembly only after proving the wiring is intact.
  • Retest fuel trims, warm restart behavior, and throttle response because those secondary symptoms often clean up right after the real fix.
Vehicle context

Affected brands in this MVP

Brand hubs help broaden internal linking now and can evolve into make-specific diagnostic notes later.

Aliases and common searches

English phrases tied to P0113

Useful when the driver knows the wording but not the exact DTC yet.

  • intake air temperature circuit high input
  • IAT high voltage
  • IAT sensor reads cold all the time
Related search intent

Queries this page can answer naturally

  • P0113 code meaning
  • what does P0113 mean
  • intake air temp circuit high input
  • IAT reading too cold
FAQ

Quick questions about P0113

Can P0113 cause rich running?

Yes. If the ECU believes the intake air is much colder than reality, it may command extra fuel or skew load calculations in a richer direction.

Is unplugging the sensor enough to trigger P0113?

Absolutely. An open circuit or unplugged connector is one of the most common reasons this code appears.

How do I separate P0113 from P0118?

Compare both intake-air and coolant-temperature readings on a cold start. One may be false while the other still looks believable.