Ambient Air Temperature Sensor
The ambient air temperature sensor is reporting a fault.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The ambient air temperature sensor, located outside the vehicle, measures the temperature of the surrounding air. If it fails or sends an incorrect reading, the engine control unit (ECU) can't adjust fuel-air mix properly, which can affect performance and emissions.
What the computer is actually seeing
The ECU expects a voltage signal between 0.5V (at -40°C) and 4.5V (at 125°C). If it sees values outside this range or a continuous open/short, it triggers a fault.
What a healthy reading looks like
Expected voltage range from the sensor is 0.5V to 4.5V depending on ambient temp, with a typical reading of about 20°C giving ~2.5V.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check the ambient air temperature sensor wiring for damage or corrosion.
- 2Verify the connector is secure and clean of any dirt or moisture.
- 3Measure the voltage at the ambient air temperature sensor with the key on and engine off; it should be in the range of 0.5V to 4.5V.
- 4If voltage is outside this range, replace the sensor and retest.
- 5If voltage is normal, check the ECU for faults or erroneous data.
Common causes
- Faulty ambient air temperature sensor
- Wiring issues (shorts, opens)
- Bad connections at the sensor or ECU
- Corrosion or dirt affecting sensor performance
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code present?
Yes, but performance may suffer and fuel efficiency can decrease.
Will the code come back after I fix it?
If the actual issue is resolved and the sensor is functioning, the code should clear after some driving cycles.
Why does this code appear with other codes?
Temperature readings can impact several systems, so a fault in the ambient temperature sensor can lead to other related faults.
Working a real vehicle right now?
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