P0243 Code Meaning and Next Steps

First checks take 10 minutes for basic checks. No special tools are usually needed for the first checks.

Can you keep driving?

Stop driving if any of these apply

!The vehicle suddenly runs much worse, loses power sharply, or the check-engine light starts flashing.
!There is a strong smell, smoke, overheating, or any symptom that suggests a real-time safety problem rather than a stored code alone.

If the light is steady and the vehicle still drives normally: Often yes for a short time, but it should not be ignored if drivability changes are obvious.

What to check first

Step-by-step checks

1
Safety first
Let the engine cool before touching turbo, exhaust, or charge-air parts
2
Free - no tools
Inspect the solenoid connector and vacuum hoses for cracks, loose fitment, or heat damage
3
Basic tool needed
Check whether the vehicle is stuck in low boost or has erratic power delivery
4
Basic tool needed
Listen for the solenoid clicking or check commanded behavior with a scan tool if available
5
Basic tool needed
If the fault appeared after engine-bay work, recheck the hose routing and connector locking
6
Basic tool needed
Make sure the solenoid is receiving proper power and ground before replacing the part

If the code returns

-If the solenoid has no power or ground, repair the circuit before replacing the valve.
-If the solenoid tests electrically but does not move or pass air correctly, replace it.
-If the vacuum system is leaking, solve that problem even if the solenoid itself still clicks.

Background

What this code means

P0243 is a generic OBD-II code for a boost control solenoid circuit malfunction.

The ECU is not happy with the control valve that helps manage turbo boost. That can be an electrical fault, a sticky solenoid, or a vacuum plumbing issue that prevents the valve from doing its job.

Diagnosis

Common causes

Most common

Failed boost control solenoid

The valve may no longer switch reliably between boost-control states.

Common

Wiring or connector fault

An open, short, or poor terminal fit can stop the solenoid from working as commanded.

Common

Vacuum hose leak

A leak can keep the boost-control circuit from moving the wastegate correctly.

Possible

Vacuum routing or install problem

Incorrect hose routing can create a fault even when the solenoid itself is still okay.

Avoid these mistakes

What not to do

xDo not replace the turbo or wastegate first if the solenoid circuit itself is obviously faulty.
xDo not ignore a vacuum routing mistake if the fault began after recent repairs.

Parts

Parts that may need replacing

PartTypical costNotes

Boost control solenoid$40-$180Most relevant when the valve no longer switches properly.

Vacuum hose set$10-$90Often part of the fix when the hose routing or seals are the real problem.

Connector or wiring repair$20-$160Important when the control circuit is electrically unstable.

Related OBD codes

P0240

P0240 means the boost control system is not behaving as expected.

P0241

P0241 means the boost control signal is reading too low.

P0242

P0242 means the boost control signal is reading too high.

Source notes

Generic OBD-II (SAE J1979 / ISO 15031-5). P0243 was seeded from dtcdb and then expanded around boost control solenoid circuit faults, with common vacuum plumbing and electrical follow-up checks.

This guide is written as a generic multi-make reference, so bulletin history, sensor locations, and repair order can still change by manufacturer and engine family.

This is generic OBD-II guidance and should not override vehicle-specific service information. Exact diagnosis and repair steps vary by make, engine family, and model year.

Last reviewed: 2026-04-10

Reference: Open reference

P0243 - The Boost Control Solenoid Circuit Has a Fault