Code result
P25FB
Turbocharger/Supercharger Bypass Valve C Control Circuit Range/Performance
Moderate severity
What it means
The third bypass valve current does not match the commanded value within tolerance. Drifted coil resistance or high-resistance contact in the connector.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Coil resistance changed by thermal stress
mediumA plausible cause — test and verify before replacing parts.
High-resistance contact in the valve connector
mediumA plausible cause — test and verify before replacing parts.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Related help
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