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

P25B1

Fuel Level Sensor B Stuck

Same condition as sensor A stuck, applied to the second fuel level sensor B. Saddle tanks (often AWD vehicles) and large trucks use two sensors — one per tank chamber — averaged for total level. A stuck B leaves only A and reduces accuracy.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number5 / B1

Possible causes

  • Stuck float high

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended
  • Estimated cost: 200–800 €
  • Estimated time: 1–3 h
  • Component: fuel level sensor b
  • MIL / check engine light
  • emissions-relevant

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