U05A1NOx Sensor A Received Invalid Data From ECM/PCM
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- Here the fault is judged inside NOx sensor A: its control unit relies on engine controller frames, for instance the release to heat the probe once condensation is no longer a risk, and it reports back when those inputs are missing or make no sense. Ford's 2023 diesel OBD summary groups U05A1 with P2200 under the upstream NOx module checks. Typical triggers are a dew point release received while the ignition is off, or no message for more than 1 s; 5 s of fault are needed to register it. Ford's 2014 code list flags it as a MIL code. CARB 1968.2 asks that digital outputs to a component be checked for communication errors. U059E is the opposite direction, U05A2 and U05A9 cover sensors B and C. The probe may stay cold, leaving NOx readings and SCR monitoring unavailable.
- What you may notice
- Check engine light on
- NOx reading for sensor A stays invalid on the scan tool
- SCR monitors not completing
- Likely causes
- PossibleEngine controller software or configuration sending wrong values to the sensor
- PossibleIntermittent CAN connection to the sensor causing timeouts
- PossibleSensor control unit misjudging correct data
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €100 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.