Diesel particulate filter (DPF)
P244A, P244B and P2452–P2455: DPF differential pressure
P244A and P244B assess differential pressure itself. P2452 to P2455 instead concern pressure sensor A’s circuit, operating range or signal level.
At a glance
What the codes tell you
- P244A
- Particulate filter differential pressure too low.
- P244B
- Particulate filter differential pressure too high.
- P2452
- Particulate filter pressure sensor A—circuit.
- P2453
- Particulate filter pressure sensor A—range/performance.
- P2454
- Particulate filter pressure sensor A—signal low.
- P2455
- Particulate filter pressure sensor A—signal high.
How the entries differ
- P244A and P244B distinguish differential pressure assessed as too low from pressure assessed as too high.
- P2452 names the circuit; P2453 concerns its range or performance.
- P2454 and P2455 distinguish a low sensor signal from a high one.
What is not yet established
- A pressure code does not prove filter loading or sensor failure.
- Pressure hoses, electrical supply, reference conditions and actual exhaust backpressure need separate assessment.
- The code describes the control unit’s assessment. It determines neither which component needs replacing nor the repair required.
- Manufacturer-specific descriptions, status, freeze-frame data and live readings can materially change the interpretation.
Diagnostic information that helps next
A reliable assessment does not consider the code in isolation. The following information turns a number into a fault condition that can be investigated:
- Differential pressure with the engine off, at idle and at a defined raised engine speed
- Sensor supply, ground and signal behaviour
- Condition and routing of pressure hoses
- Loading values, temperatures and other DPF codes stored at the same time
More codes for this system
Frequently asked questions about P244A, P244B, P2452, P2453, P2454, P2455
What do fault codes P244A, P244B, P2452, P2453, P2454, P2455 mean?
P244A: Particulate filter differential pressure too low. P244B: Particulate filter differential pressure too high. P2452: Particulate filter pressure sensor A—circuit. P2453: Particulate filter pressure sensor A—range/performance. P2454: Particulate filter pressure sensor A—signal low. P2455: Particulate filter pressure sensor A—signal high.
Which component needs replacing for P244A?
The code does not determine that. The full diagnostic description, fault status, freeze-frame data, live readings and vehicle-specific system checks determine the appropriate repair.
What information helps with diagnosis?
Useful information includes Differential pressure with the engine off, at idle and at a defined raised engine speed, Sensor supply, ground and signal behaviour, Condition and routing of pressure hoses, Loading values, temperatures and other DPF codes stored at the same time.
Traceable sources
Sources and scope
The descriptions are our own factual explanations of standardised generic OBD definitions. Manufacturer-specific P1xxx codes and differing manufacturer descriptions are not given blanket interpretations here.