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

P050F

Brake Assist Vacuum Too Low

The ECU monitors the vacuum supplied to the brake booster (either via a dedicated sensor or via intake manifold pressure). The level has dropped below the calibrated threshold; brake-pedal feel will be hard, and an electric vacuum pump may be commanded to restore vacuum.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number5 / 0F

Possible causes

  • Vacuum leak in booster line or check valve high
  • Electric vacuum pump weak medium

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 120–700 €
  • Estimated time: 0.8–3 h
  • Component: brake booster
  • Component: vacuum pump
  • Component: vacuum check valve
  • MIL / check engine light

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