Fault codeP242F

MODERATE

Diesel Particulate Filter Restriction - Ash Accumulation (Bank 1)

What this code means

Diesel Particulate Filter Restriction - Ash Accumulation (Bank 1).

“Bank 1” is the side of the engine that holds cylinder number 1; “Bank 2” only exists on V and flat engines. An in-line engine has a single bank.

P242F is a generic code: it means the same thing on every make. P242F belongs to family P24xx — Auxiliary emission controls. Its page explains how to read a code and groups all its codes by part.

Diesel particulate filter (DPF)

The particulate filter, in the exhaust of diesel engines, traps soot. It cleans itself by burning that soot during regenerations: the control unit raises the exhaust temperature for a few minutes, usually during a steady drive. A differential pressure sensor measures how clogged the filter is.

What you notice

Loss of power or limp mode, a particulate filter warning on the dashboard, a cooling fan still running after the engine is switched off, higher consumption when regenerations become frequent.

How to check it

Short trips prevent regeneration: twenty minutes at a steady speed on a main road often lets it complete. Then check the differential pressure sensor and its two small pipes, which crack or fill with soot, and look for what produces too much soot (EGR valve, injectors, turbo). A filter full of ash after many kilometres can only be cleaned or replaced.

Watch it live in Klaro

With an OBD2 adapter plugged in, these live readings show the part at work, when your car reports them:

DPF differential pressure, bank 1
DPF inlet temperature, bank 1
DPF outlet temperature, bank 1
Vehicle speed

What to do

Have it checked this week. The car remains usable, but the fault will not clear itself and will fail the roadworthiness test.

Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →

How to read this code

PPowertrain
2standardised code
4Auxiliary emission controls
2FP242F