P0246: Turbocharger/Supercharger Wastegate Solenoid "A" High
The voltage in the wastegate solenoid A circuit is higher than expected.
High risk
Usually drivable, but power is usually limited. Have it checked soon.
Short answer · Can I keep driving with P0246?
Usually yes, at reduced power. Without control of the wastegate the engine limits boost to protect itself. Have it checked soon.
What does P0246 mean?
P0246 means the voltage in the wastegate solenoid circuit is higher than expected. A short to voltage, an open ground or a fault in the control unit output are typical causes. The wastegate solenoid controls the vacuum or pressure that moves the wastegate, which sets how much exhaust bypasses the turbine. On cars with an electric wastegate actuator, the same code covers the actuator motor circuit.
What the car does when the code is set
The check engine light comes on and the engine control unit limits power (limp mode). The car still drives but accelerates slowly. The limitation is usually lifted when the engine is restarted, until the fault appears again.
How the system works
A turbocharger uses exhaust gas to drive a compressor that pushes more air into the engine. The amount of boost is controlled either by a wastegate, which lets exhaust bypass the turbine, or by variable vanes that change how the exhaust strikes it. The engine control unit sets a target boost pressure and moves the actuator to reach it, measuring the result with a boost pressure sensor. If the measured pressure exceeds the maximum allowed, it stores an overboost code and limits power to protect the engine.
Common symptoms
Possible causes
Listed without ranking. The cause on your car depends on make, engine and mileage — see the maker notes below.
- Stuck wastegate or variable vanesThe turbo cannot reduce boost.
- Faulty boost control solenoidThe solenoid does not regulate the vacuum or pressure to the actuator.
- Damaged control hosesA split or swapped vacuum hose on the boost control.
- Faulty boost pressure sensorThe sensor reads higher than the real pressure.
How it is diagnosed
- Check the hosesInspect vacuum and pressure hoses of the boost control for splits and correct routing.
- Test the actuatorCheck that the wastegate or vane actuator moves freely across its whole range.
- Compare boost readingsCompare desired and actual boost with live data, and the sensor reading with the outside air pressure with the engine off.
- Test the control solenoidCheck resistance and operation as described in the service data.
Questions about P0246
Can I test the wastegate solenoid?
With the connector off, the solenoid coil should show the resistance given in the service data. A scan tool can also switch it on and off: a working solenoid clicks, and on vacuum systems the wastegate rod moves.
Why does the car go into limp mode?
To protect the engine from too much boost, the control unit limits power until the fault is fixed.
Can a chip tune cause overboost codes?
Yes. Modified software or boost controllers can exceed the sensor's or engine's limits and set this code.
Is this a turbo failure?
Usually not. The turbo itself works but is not being controlled correctly.