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P0250 – Turbocharger Wastegate Solenoid B High (OBD2)

P0250 means "Turbocharger Wastegate Solenoid B High". The voltage in the turbocharger boost control circuit is above the permitted maximum. For most sensors this points to an open signal or ground wire – the signal "floats" up to the reference voltage – or to a short to voltage.

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P0250 quick summary

Fault codeP0250
MeaningTurbocharger Wastegate Solenoid B High
SystemPowertrain (Engine & Transmission)
VehiclesGeneric OBD2
SeverityHigh
Can I drive?Usually yes, but in limp mode with reduced power. Overboost or overspeed codes mean the turbo is at risk – avoid full throttle until it is repaired.
Repair cost€20 – €2,000

How turbocharger boost control works

The boost control system sets how much pressure the turbocharger produces, using a wastegate, variable vanes or a bypass valve; these codes cover their solenoids and actuators.

A turbocharger is driven by exhaust gas. To control boost, petrol engines and older diesels use a wastegate that lets exhaust bypass the turbine; most modern diesels use variable turbine geometry (VTG/VNT) vanes. They are moved by a vacuum actuator controlled by a solenoid, or by an electric actuator. Petrol turbo engines also have a bypass (diverter/recirculation) valve that releases pressure when the throttle closes.

Codes in this group cover the boost control solenoids and actuators (A and B), the bypass valve circuit and turbine overspeed (P0049). Electrical faults stop the control unit from regulating boost, so it usually goes into limp mode; performance faults mean the actuator does not achieve the commanded position.

Common causes are cracked vacuum hoses, failed control solenoids, sticking vanes due to soot, seized wastegates and worn electric actuators.

On VAG vehicles (VW, Audi, Škoda, Seat, Cupra), VCDS and older VAG testers can show this code as the five-digit VAG code 16634 (P0250). Both numbers mean the same fault.

Symptoms of P0250

  • Limp mode, loss of power
  • Check Engine light on
  • Hissing or whistling
  • Surging or jerky power delivery
  • Overboost or underboost codes alongside

Most common causes of P0250 (most likely first)

Mechanic's Pro Tip

On diesels, a few hard full-throttle pulls in a low gear sometimes free sticking turbo vanes temporarily. If that brings the power back, you have confirmed the cause – plan a vane clean before it sticks permanently.

  1. 1.Open circuit in the signal or ground wire

    Most likely

    A loose ground connection is a very common cause.

  2. 2.Signal wire shorted to the 5 V reference or battery voltage

  3. 3.Faulty turbocharger boost control

  4. 4.Cracked or disconnected vacuum hoses

    The cheapest and one of the most common causes.

  5. 5.Sticking VTG vanes or wastegate

    Soot and corrosion seize the mechanism.

  6. 6.Wiring or connector fault

Step-by-step diagnostic guide

  1. 1

    Read codes and boost data

    Read all codes and compare specified and actual boost and actuator position in live data during a full-load acceleration.

  2. 2

    Check signal and ground

    With the ignition on and the turbocharger boost control plugged in, back-probe the signal and ground wires. A signal stuck at reference or battery voltage points to an open ground/signal wire or a short to voltage.

    Multimeter: Ground wire to battery negative: below about 0.1 V. Signal stuck at about 5 V (or 12 V) = open or short to voltage.

  3. 3

    Check vacuum hoses and supply

    Check all vacuum hoses to the solenoid and actuator, and the vacuum pump output on diesels.

    Multimeter: A healthy vacuum supply on diesels is typically around 0.7–0.9 bar below atmospheric.

  4. 4

    Test the solenoid

    Measure the solenoid resistance and run the output test – it should click and the actuator should move.

    Multimeter: Many boost control solenoids read about 14–30 Ω.

  5. 5

    Check the actuator and vanes

    Disconnect the actuator rod and move the vanes or wastegate by hand – they must move freely. Test a vacuum actuator with a hand pump.

  6. 6

    Repair and calibrate

    Replace hoses, solenoid or actuator; electric actuators usually need a calibration with the scan tool.

Frequently asked questions

Can I keep driving with P0250?

Usually yes, but in limp mode with reduced power. Overboost or overspeed codes mean the turbo is at risk – avoid full throttle until it is repaired.

How much does it cost to fix P0250?

Typical repair costs are 20 € – 2000 €, depending on the cause and the vehicle. The most common fixes are: open circuit in the signal or ground wire; signal wire shorted to the 5 V reference or battery voltage; faulty turbocharger boost control. Always confirm the cause with the tests above before buying parts.

Does a boost control code mean my turbo is broken?

Usually not. Hoses, solenoids and actuators are far more common causes than the turbo itself.

What does turbine overspeed (P0049) mean?

The turbo spins faster than allowed, usually because boost control is not working or there is a boost leak making the turbo work harder. It must be fixed quickly to avoid turbo damage.

What is the difference between P0250 and similar codes?

P0250 belongs to a group of codes for the same component that differ in the type or location of the fault: P0247 – Turbocharger Wastegate Solenoid B Malfunction; P0248 – Turbocharger Wastegate Solenoid B Range/Performance; P0249 – Turbocharger Wastegate Solenoid B Low; P2562 – Turbocharger Boost Control Position Sensor A Circuit; P2563 – Turbocharger Boost Control Position Sensor A Range/Performance; P2564 – Turbocharger Boost Control Position Sensor A Circuit Low. The tests on this page apply to the whole group; the type of fault tells you where to start.

Related fault codes

This guide is for information only. Working on vehicles can be dangerous — if you are unsure, have the car checked by a qualified mechanic. Values can differ between model years; always check the manufacturer's repair information.