Code result
P2D1B
Exhaust Flow Control Valve C Position Not Learned
High severity
What it means
The exhaust flow control valve C reports a position not learned condition. Exhaust routing for back-pressure or noise control on this branch cannot be commanded reliably.
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
Adaptation lost after battery disconnect
highOne of the most commonly reported causes for this code — check this first.
Valve replaced without learn procedure
mediumA plausible cause — test and verify before replacing parts.
Related help
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