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.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
Common causes
Ordered by how often each turns out to be the cause.
- Alternator regulator failed (overvoltage)Common
- Connector pins corroded - high contact resistanceLess likely
- Supply wire pinched against B+ sourceLess likely
Parts involved
- Boost Actuator B Supply
- Charging System
P005F is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.