P2458Powertrain
DPF regeneration duration fault
Where to start
Regeneration of the particulate filter starts but never finishes. ⚠️ The commonest cause is not a failure but the driving: regeneration is interrupted if you switch off halfway. If the dashboard asks you to keep driving, keep driving. Repeatedly interrupted regeneration is exactly what turns into a blocked filter.
A code is not a diagnosis. It says which check failed, not which part to replace. Clearing it without repair only means the car will report it again in a few trips.
How to put together a report a mechanic will actually read
We have a detailed piece on thisThe diesel particulate filter: signs, regeneration, codes
How the code is built
Letter — the systemPowertrain: engine and transmission
Common or the maker's ownGeneric code, second group
Which part of the engineEmission controls: catalyst, EGR, fuel vapour
Number of the faultThe serial number inside that group — it does not say how serious the fault is
All codes in «Diesel particulate filter»
How the app helps
CarScan reads this code from your car through an OBD-II adapter, shows whether it is active now or only stored, names the module that reported it, and puts it into a plain-text report for your mechanic.