Powertrain
generic / SAE
P004C
Turbocharger/Supercharger Boost Control B Circuit Low
Boost control B circuit voltage below expected range. Same as P0047 on actuator B. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number– / 4C
Possible causes
- Wiring shorted to ground high
- Connector pins corroded - high contact resistance low
- Harness chafing through insulation low
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 80–600 €
- Estimated time: 0.5–3 h
- Component: boost control solenoid b
- Component: actuator wiring
- MIL / check engine light
- emissions-relevant
- drive cycle required
- limp mode possible
Sources
References
sae:J2012