Exhaust Heat Exchanger Bypass Valve B Stuck Closed
Same as P23A6 with bypass valve B stuck closed - exhaust always passes through the heat exchanger.
Affected components
- Exhaust bypass valve b
Common causes
- High likelihood: Valve stuck closed
- Low likelihood: Carbon or debris buildup preventing free movement
- Low likelihood: Component wear with age - mechanical play
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
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.