Faulty wastegate control solenoid or electric wastegate actuator; Damaged, chafed or corroded wiring or loose connector at the solenoid or actuator; Split, disconnected or perished vacuum or pressure hoses to the wastegate actuator; Stuck or seized wastegate linkage or actuator rod due to carbon build-up or heat damage; Low or unstable supply voltage or poor earth affecting the solenoid circuit; Fault in the engine control unit driver circuit or outdated software calibration where the manufacturer has issued an update.

P0243

Turbocharger/Supercharger Wastegate Actuator A.

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)
43: FaultThe specific fault in that area

What it means

P0243 is the generic code for a fault in the turbocharger or supercharger wastegate solenoid 'A' circuit or its control. The engine control unit has seen an electrical fault in the wastegate solenoid or its wiring, or a mismatch between commanded and actual wastegate or boost behaviour. Exact detection logic and whether the actuator is electric, vacuum or pressure operated depends on the make, model and engine.

Symptoms

Engine warning light on
Loss of power or reduced boost
Car going into limp mode
Poor acceleration or hesitation under load
Overboost or inconsistent boost pressure
Whistling or hissing from a vacuum or boost leak

Possible causes

Faulty wastegate control solenoid or electric wastegate actuatorlikely
Damaged, chafed or corroded wiring or loose connector at the solenoid or actuatorlikely
Split, disconnected or perished vacuum or pressure hoses to the wastegate actuatorlikely
Stuck or seized wastegate linkage or actuator rod due to carbon build-up or heat damagepossible
Low or unstable supply voltage or poor earth affecting the solenoid circuitpossible
Fault in the engine control unit driver circuit or outdated software calibration where the manufacturer has issued an updaterare

How to diagnose

Read all stored and pending codes and review freeze frame data for load, rpm and boost at the time of the fault
Check for related codes such as boost pressure, overboost or underboost faults, and check for any manufacturer technical bulletins for the model and engine
Visually inspect the solenoid, actuator, wiring and connectors for damage, heat, oil contamination, corrosion or chafing
Inspect all vacuum and boost hoses to the wastegate for splits, loose fittings and routing faults, and check for boost leaks
Check the wastegate linkage moves freely and fully by hand where accessible, with the engine off and cool
Using a multimeter or scope, test the solenoid or actuator for supply, earth, control signal and coil resistance against the specification for that model
Use a bidirectional scan function to command the wastegate and confirm it responds and that measured boost follows
Test the vacuum or pressure supply to the actuator where fitted, and check the vacuum pump on applicable engines

How to fix

Replace the faulty wastegate solenoid or electric actuator, then carry out any adaptation or learning procedure the manufacturer requires
Repair or replace damaged wiring, terminals or connectors
Replace split or perished hoses and secure all fittings
Free or replace a seized wastegate linkage or actuator, which may mean replacing the turbocharger on some designs
Correct charging, battery or earth faults affecting the circuit
Apply a manufacturer-approved software update only if a known calibration fault applies to the vehicle

Can I keep driving?

Medium severity

The car can usually be driven carefully for a short time, often in limp mode with reduced power, but get it checked soon. Uncontrolled overboost can damage the engine or turbocharger, so avoid heavy loads and stop driving if power surges or the car runs rough.

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