OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Powertrain generic / SAE

P2458

DPF Regeneration Duration

The DPF regeneration cycle takes longer than the calibrated maximum. The ECU sets this code when the soot load is not being burned off within the expected window — common after many short trips or with degraded post-injection.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / 58

Possible causes

  • Heavy soot load, short trips high
  • Post-injection insufficient medium

Symptoms

  • Check engine light or DPF warning light on
  • Power loss / limp mode
  • Increased fuel consumption
  • Failed forced regeneration attempts

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended
  • Estimated cost: 150–1500 €
  • Estimated time: 0.5–4 h
  • Component: diesel particulate filter
  • Component: dpf temperature sensor
  • Component: fuel injectors
  • MIL / check engine light
  • emissions-relevant
  • drive cycle required
  • limp mode possible

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication