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

P2002

Diesel Particulate Filter Efficiency Below Threshold (Bank 1)

Diesel Particulate Filter Efficiency Below Threshold (Bank 1): the control module has detected this fault condition.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / 02

Possible causes

  • DPF heavily loaded — repeated short trips prevent regeneration high
  • Filter substrate cracked or melted from runaway regeneration medium
  • Differential pressure sensor drift medium
  • Leak around DPF housing low

Symptoms

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

Inspection / repair

  • Difficulty: hard
  • DIY: shop recommended
  • Estimated cost: 400–4000 €
  • Estimated time: 2–8 h
  • Component: diesel particulate filter
  • Component: dpf differential pressure sensor
  • Component: dpf temperature sensor
  • 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