P0071
Ambient Air Temperature Sensor Circuit A Range/Performance
The ambient air temperature reading is electrically valid but implausible compared to other temperature sources (intake air temp, coolant at cold start).
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: easy
Common causes
Ordered by how often each turns out to be the cause.
- Sensor reading driftedCommon
- Sensor exposed to engine heatPossible
- Sensor element aged beyond calibration windowLess likely
Parts involved
- Ambient Air Temp Sensor
P0071 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.