P0046
Turbocharger/Supercharger Boost Control A Circuit Range/Performance
Boost control actuator A is electrically active but boost pressure deviates from target. Mechanical or hydraulic limitation.
- 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.
- Vacuum/boost line leakCommon
- Wastegate stickingPossible
- Sensor element aged beyond calibration windowLess likely
Parts involved
- Boost Control Solenoid
- Wastegate
- Vacuum Lines
P0046 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.