P2228Barometric Pressure Sensor A Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2228 sets when the voltage from barometric pressure sensor A stays below the lowest value a real atmosphere could produce. Ford's gasoline summaries (2012 and 2020-2023) use under 2.0 V, which would mean an altitude above 15,000 ft, for 5 s; on these engines the sensor is mounted on the PCM circuit board. Ford's 2023 diesels flag under 0.25 V (about 6 kPa) after 0.5 s. GM's 2018 diesel tables attribute it to a grounded or broken signal line on a pull-down input: below 35.5 % of the 5 V supply (equal to 50 kPa) in 320 of 400 readings, Type B with the MIL after two trips. In Ford's 2024 software the same fault appears as P2226-16. P2229 is the high counterpart. The engine runs on a substitute pressure, so drivers mostly see only the lamp.
- What you may notice
- Check engine light
- Auto start-stop deactivated
- Scan tool shows an implausibly low barometric pressure
- Likely causes
- PossibleSignal wire of an external BARO sensor shorted to ground or open
- PossibleDefective sensor inside the PCM (Ford, Mazda and others), PCM replacement
- RareLow or missing 5 V reference to the sensor
- 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: €50 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.