P2C29
- Powertrain
- Manufacturer-specific
- Emissions
Get it looked at now
Driving may cause further damage or leave you stranded. Arrange service promptly rather than waiting.
Turbocharger/Supercharger Bypass Valve B Stuck
This code is in our catalogue but has not yet been through editorial review, so the guidance below is limited to what our structured data supports. We publish deeper diagnostic content only after a code has been reviewed — here is why.
The turbocharger/supercharger bypass valve B reports a stuck condition. Boost recirculation cannot be commanded reliably on this branch.
A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.
- Safe to drive
- Driving may cause further damage or leave you stranded. Arrange service promptly rather than waiting.
- Urgency
- Get it looked at now
- Will it pass emissions
- No
- Check engine light
- Solid
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
Many vehicles show no symptom at all beyond the warning light. The absence of a symptom does not mean the fault is not real.
| # | Cause | How often | Component |
|---|---|---|---|
| 1 | Bypass valve mechanically seized | Very common | — |
| 2 | Carbon deposits jam the valve | Common | — |
Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.
- Turbo Bypass Valve B
- Wiring Harness
- ECM
- Definition
- Generic code set (SAE J2012 / ISO 15031-6) via the OBDexopen database, dedicated to the public domain under CC0-1.0.
- Diagnostic guidance
- Written and reviewed in-house. See our editorial policy.
- Review status
- Awaiting review
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