P0047–P004C Turbocharger/Supercharger Boost Control A Circuit Low
The voltage on this circuit is sitting near zero. Typically a short to earth, or a sensor that has failed to its low end.
Can you drive it? The car is most likely in limp mode with boost cut. It is drivable gently, but it will not make full power and should not be driven hard until it is fixed.
Which code is which
Same fault, different cylinder or bank — diagnosed the same way. Several set together usually means one shared cause.
| Code | Definition | Severity |
|---|---|---|
P0047 | Turbocharger/Supercharger Boost Control A Circuit Low | Investigate soon |
P004C | Turbocharger/Supercharger Boost Control B Circuit Low | Investigate soon |
The definition
P0047: Turbocharger/Supercharger Boost Control A Circuit Low.
P0047 is a powertrain code (the engine or gearbox), defined by the SAE standard - it means the same thing on any make of car, and any generic OBD-II reader will decode it.
What to check first
Cheapest and fastest checks first:
- Unplug the sensor. If the reading jumps to full scale, the wiring is fine and the sensor has failed low.
- Check the sensor's 5V supply and its earth before condemning the sensor itself.
Reading the code is the easy part
A code names the circuit that complained. What tells you why is watching the sensor behind it while the engine runs — and that is where a code reader stops and a diagnostic tool starts.
VAGPULSE reads every module in a VW, Audi, Skoda or SEAT — not just the engine — shows the live measuring blocks behind this fault, gives you the freeze-frame conditions it was logged under, and clears it once you have fixed it. It also does what a generic OBD reader cannot on a VAG: service resets, coding, adaptations, and Stage 1–3 flashing with your original file saved first.
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Common questions
What does P0047 mean?
P0047 means Turbocharger/Supercharger Boost Control A Circuit Low. The voltage on this circuit is sitting near zero. Typically a short to earth, or a sensor that has failed to its low end.
Can I drive with P0047?
The car is most likely in limp mode with boost cut. It is drivable gently, but it will not make full power and should not be driven hard until it is fixed.