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

P04B6

Fuel Fill Door Stuck Closed

Same as P04B5 with the door stuck closed - the user cannot refuel until the fault is cleared.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number4 / B6

Possible causes

  • Latch jammed or actuator stalled high
  • Carbon or debris buildup preventing free movement low
  • Component wear with age - mechanical play low

Inspection / repair

  • Difficulty: easy
  • DIY: possible
  • Estimated cost: 60–250 €
  • Estimated time: 0.4–1.2 h
  • Component: fuel fill door
  • Component: fuel fill door actuator

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