Code result
P00C4
Turbocharger/Supercharger Bypass Valve B - Mechanical
High severity
What it means
Mechanical fault detected at bypass valve B — broken linkage, jammed valve, or seized actuator rod. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Linkage broken or seized
highOne of the most commonly reported causes for this code — check this first.
Related help
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