Intake Air Temperature Circuit High Input
Your engine's intake air temperature sensor is reading hotter than it should, like a thermometer stuck on a high number. The ECU thinks the incoming air is too warm, which throws off fuel calculations.
The ECU monitors voltage from the Intake Air Temperature (IAT) sensor, which uses a thermistor that changes resistance based on air temp. High voltage signals indicate cold air; low voltage indicates hot air. A 'high input' fault means the ECU sees a voltage signal above its maximum expected threshold, typically indicating a sensor or wiring fault rather than actual high temperatures.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| IAT Sensor Voltage | 0.5–4.5V (depending on actual temp) | >4.5V or open circuit condition |
| IAT Temperature Reading | -40°C to 125°C | Below -40°C equivalent voltage |
Code P0113 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P0113 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.