Exhaust Flow Control Valve B Position Not Learned
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.
Affected components
- Exhaust flow control valve b
- Ecm
Common causes
- High likelihood: Adaptation lost after battery disconnect or ECM reset
- Medium likelihood: Valve replaced without learn procedure
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.