OBD Codes List

Diagnostic reference · P004F

P004F

Turbocharger/Supercharger Boost Control B Circuit Intermittent/Erratic

System
Fuel and air metering (P code)
Lamp
Check Engine Light
Category
Powertrain - Fuel/Air Metering

What it means

P004F means Turbocharger/Supercharger Boost Control B Circuit Intermittent/Erratic.

Check these first

  • An intermittent open in the boost control B wiring or connector
  • A failing boost control B solenoid
  • A boost pressure sensor with an erratic signal
  • A sticking wastegate actuator
  • A loose boost control B ground

What to do next

  1. Wiggle test the boost control B harness while watching the data
  2. Measure the boost control B solenoid resistance
  3. Compare boost pressure sensor readings to a gauge
  4. Check the wastegate actuator for sticking
  5. Check the boost control B ground for tightness
  6. Clear the code and retest

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Updated

Generic SAE J2012 definition. Last updated 2026-10-10.