P244B: Diesel particulate filter differential pressure too high (bank 1)
The pressure difference across the diesel particulate filter is higher than normal. Usually a heavily sooted filter or a blocked sensor tapping.
| Code | P244B |
|---|---|
| System | Engine and transmission |
| Group | P24xx, EGR, EVAP and particulate filter |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What P244B means
A sensor compares exhaust pressure before and after the particulate filter. If the difference is very large, the gases are meeting too much resistance: the filter is heavily loaded with soot or ash, or the sensor is giving a reading that is not real.
Most common causes
- Filter heavily loaded because regenerations never finish (lots of short trips)
- Sensor pipe or tapping blocked with soot
- Faulty differential pressure sensor
- High ash load in the filter
- Engine problem producing excess soot: injector, EGR or intake leak
Symptoms
- Engine or DPF warning light on
- Loss of power or limp mode
- Fan running after switch-off or raised idle (regeneration in progress)
- Higher fuel consumption
Can you drive with P244B?
With care You can drive with care, but get to a garage soon. If left, the filter keeps filling and may reach a point where it can only be regenerated or cleaned by a workshop.
How to check it
Check the differential pressure and estimated soot load on your scanner. If soot is high and the car allows it, a steady 20 to 30 minute motorway run helps a regeneration finish.
How to read and clear P244B with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P244B with this same explanation and whether it’s confirmed, pending or permanent.
With Free you read this code with its short description for nothing, and clear it if the engine stores it over standard OBD. With Pro you get the full explanation, how the car was running when it was logged (revs, temperature, load) and clearing in every control unit.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before the ITV. It’s all in how to read and clear fault codes and in the ITV and OBD.
Similar codes
- P2414 O2 sensor exhaust sample error (bank 1, sensor 1)
- P2425 EGR cooler valve control circuit open or faulty
- P242F Diesel particulate filter restriction: ash accumulation
- P244A Diesel particulate filter differential pressure too low (bank 1)
- P2452 Diesel particulate filter pressure sensor A circuit
- P2453 Diesel particulate filter pressure sensor A range/performance
- P2454 Diesel particulate filter pressure sensor A circuit low
- P2455 Diesel particulate filter pressure sensor A circuit high
- P2400 EVAP leak detection pump control circuit open or faulty
- P2413 Exhaust gas recirculation (EGR) system performance
- P2458 Diesel particulate filter regeneration duration
- P2459 Diesel particulate filter regeneration frequency
P244B is a generic code, so it means the same on any make, for example on BMW, Citroën, Ford, Mercedes-Benz, Renault, Volvo. See what Final OBD does on your car in makes and models.
What does code P244B mean?
A sensor compares exhaust pressure before and after the particulate filter. If the difference is very large, the gases are meeting too much resistance: the filter is heavily loaded with soot or ash, or the sensor is giving a reading that is not real.
Can you drive with P244B?
You can drive with care, but get to a garage soon. If left, the filter keeps filling and may reach a point where it can only be regenerated or cleaned by a workshop.
How do you clear P244B?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P244B comes back.
Read it on your car
Final OBD reads the faults of every control unit for free, including each make’s own codes, and with Pro explains each one in plain English. Free clears engine faults at no cost.
Coming soon
Mid to late October 2026
If you want to try it in your car before anyone else, send us your email and we will add you as a tester.
info@finalobd.com