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

P2BB0

Alternative Fuel Consumption Too Low

The AFCM detects that alternative fuel consumption falls below the expected value for the active operating mode. Indicates injector clogging, leaks before injectors, or incorrect tank-fill correction.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / numberB / B0

Possible causes

  • Alt fuel injectors partially clogged high
  • Tank-fill calibration drifted medium

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended
  • Estimated cost: 200–1500 €
  • Estimated time: 1–6 h
  • Component: alt fuel injectors
  • Component: alt fuel tank
  • Component: afcm
  • MIL / check engine light
  • emissions-relevant
  • drive cycle required

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