P246DParticulate Filter Pressure Sensor A/B Correlation
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P246D compares two pressure readings at the particulate filter that ought to agree under steady conditions. Which sensor is A and which is B is decided by each manufacturer. Ford's 2013 to 2015 diesel summaries use it as a rationality test between the filter pressure sensor DPFP and the delta pressure sensor DPS: with coolant above 70 °C, ambient pressure above 745 hPa, filter inlet temperature between 125 and 425 °C and exhaust flow of 200 to 600 kg/h, the code sets once the two differ by over 1.5 kPa, evaluated over about 2 s. Typical findings are swapped, kinked or leaking sensing hoses, water in a line or one sensor drifting while its circuit still passes. Pure electrical faults have their own codes (P2452 ff. and P245E ff.). With a doubtful pressure value the soot estimate and regeneration timing suffer.
- What you may notice
- MIL on
- Regeneration too early, too late or suspended
- Pressure values of the two sensors disagree in live data
- Likely causes
- LikelySensing hoses swapped, kinked or leaking
- PossibleWater or soot in a sensing line
- PossibleOne pressure sensor drifting out of calibration
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €20 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.