OBD-II code · Powertrain (generic)

P005F Turbocharger/Supercharger Boost Control B Supply Voltage Circuit High

Supply voltage feeding boost control actuator B is above the expected range. Likely charging system overvoltage or wiring shorted to a higher potential.

Is it safe to drive with P005F?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyAlternator regulator failed (overvoltage)
  • Less likelyConnector pins corroded - high contact resistance
  • Less likelySupply wire pinched against B+ source

Symptoms

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

Repair at a glance

Difficulty
Medium
DIY friendly
Often, with basic tools
Typical labour
0.5–3 h
Emissions test
Likely to fail
Parts involved
Boost Actuator B Supply, Charging System

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.