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

P259C

Excessive Time To Enter Closed Loop Turbocharger A Boost Control

After start-up the boost-control loop on turbo A takes longer than the calibration limit to transition from open-loop to closed-loop control. Typically a slow-warming actuator (VGT vanes carbonised), a sluggish position sensor or a leaky pneumatic actuator that cannot follow setpoints quickly enough.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number5 / 9C

Possible causes

  • Carbonised VGT vanes high
  • Leaky pneumatic actuator medium

Symptoms

  • Charge status indicator shows fault
  • Charging may not start or interrupts
  • Slower-than-expected charge rate

Inspection / repair

  • Difficulty: hard
  • DIY: shop recommended
  • Estimated cost: 300–2200 €
  • Estimated time: 1–5 h
  • Component: turbo actuator a
  • 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