Wiring fault in the actuator or solenoid B control circuit, such as a short to voltage, chafing or an open circuit; Corroded, loose or damaged connector at the wastegate solenoid or actuator; Faulty wastegate solenoid or electric actuator B (internal fault or stuck); Mechanical fault such as a stuck wastegate flap, seized linkage or damaged vacuum or pressure lines, depending on the system type; Low or unstable supply voltage or a poor earth affecting the circuit; Fault in the engine control unit output driver; Outdated control unit software where the manufacturer has issued a fix for this fault.

P0250

Turbocharger/Supercharger Wastegate Actuator B High.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
2: AreaFuel and air metering (injector circuit)
50: FaultThe specific fault in that area

What it means

P0250 means the engine control unit has detected a high signal or voltage on the control circuit for wastegate actuator (or solenoid) 'B' on a turbocharged or supercharged engine. The unit monitors the circuit and sets the code when the voltage or feedback is higher than expected for the commanded state. Which turbo or wastegate is 'B' depends on the model and engine layout, so check the manufacturer data.

Symptoms

Engine warning light on
Loss of power or reduced boost, possibly limp mode
Overboost or boost that surges and is unstable
Poor acceleration or hesitation under load
Whistling or fluttering noises from the turbo area
Higher fuel consumption

Possible causes

Wiring fault in the actuator or solenoid B control circuit, such as a short to voltage, chafing or an open circuitlikely
Corroded, loose or damaged connector at the wastegate solenoid or actuatorlikely
Faulty wastegate solenoid or electric actuator B (internal fault or stuck)likely
Mechanical fault such as a stuck wastegate flap, seized linkage or damaged vacuum or pressure lines, depending on the system typepossible
Low or unstable supply voltage or a poor earth affecting the circuitpossible
Fault in the engine control unit output driverrare
Outdated control unit software where the manufacturer has issued a fix for this faultrare

How to diagnose

Read all stored and pending codes and the freeze frame data, noting load, rpm and boost at the time of setting. Look for related boost or turbo codes.
Visually inspect the turbo area wiring, connectors and any vacuum or pressure hoses for heat damage, chafing, oil contamination or disconnection.
Check the battery condition and charging voltage, and the relevant earth connections.
With the ignition on, check the wiring diagram for the model and test the supply voltage, earth and signal at the solenoid or actuator connector.
Check the control wiring for short to voltage and for continuity back to the control unit, wiggling the harness to reveal intermittent faults.
Measure the solenoid resistance, or run an actuator test through a scan tool, and compare with the manufacturer specification.
Check the wastegate linkage and actuator rod move freely and are not seized or carbon-bound.
Check for software updates or technical bulletins for the vehicle before suspecting the control unit.

How to fix

Repair or replace damaged wiring and renew faulty connector terminals.
Replace the wastegate solenoid or actuator if it fails electrical or functional tests.
Free up or replace a seized wastegate linkage, or repair the turbo assembly if the wastegate itself is faulty.
Replace split, loose or disconnected vacuum or pressure lines.
Correct battery, charging or earth problems.
Update the control unit software only where the manufacturer lists it as a fix, or replace the control unit if a confirmed fault is found.

Can I keep driving?

Medium severity

The car can usually be driven for a short time, often in limp mode with reduced power, but get it checked soon. Uncontrolled boost can harm the engine or turbo, so avoid heavy loads if it surges or overboosts.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.