Code result
P2D12
Exhaust Flow Control Valve B Position Not Learned
Moderate severity
What it means
The ECM has not learned the end-stop calibration for exhaust flow control valve B. Position cannot be commanded with full precision until adaptation completes.
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
Adaptation lost after battery disconnect or ECM reset
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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