MasterTuning Fault code dictionary (DTC)

P242F — DPF restriction - ash accumulation

Severity: Serious Can you drive? With caution: limp mode possible, have it checked soon Make: All makes (OBD-II standard)
MeaningThe filter is blocked by ash rather than soot. Ash is the residue left after every regeneration and it does not burn: it builds up permanently and regeneration cycles cannot remove it.
FamilyPowertrain (P)

Typical symptoms

Engine warning light on
Increasingly frequent regenerations
Reduced power
The code returns shortly after a forced regeneration

Common causes

High mileage: ash builds up naturally
Engine oil burnt through wear or overfilling
Oil that does not meet low-SAPS specification

What to do

A forced regeneration will not fix this, because ash does not burn: the filter needs off-car hydrodynamic cleaning or, in extreme cases, replacement. First, check that the engine is not consuming oil, otherwise the problem comes straight back.

Frequently asked questions

What does code P242F mean?

DPF restriction - ash accumulation. The filter is blocked by ash rather than soot. Ash is the residue left after every regeneration and it does not burn: it builds up permanently and regeneration cycles cannot remove it.

Can I keep driving with code P242F active?

With caution: limp mode possible, have it checked soon

Common causes — P242F

High mileage: ash builds up naturally Engine oil burnt through wear or overfilling Oil that does not meet low-SAPS specification

How do you fix code P242F?

A forced regeneration will not fix this, because ash does not burn: the filter needs off-car hydrodynamic cleaning or, in extreme cases, replacement. First, check that the engine is not consuming oil, otherwise the problem comes straight back.

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