OBD-II code · Powertrain (generic)
P00C1 Turbocharger/Supercharger Bypass Valve B Control Circuit Low
Bypass valve B control voltage below expected range — short to ground. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.
Is it safe to drive with P00C1?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyWiring shorted to ground
- Less likelyConnector pins corroded - high contact resistance
- Less likelyHarness chafing through insulation
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–3 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Bypass Valve B, Actuator Wiring
Related codes
- P25F9Turbocharger/Supercharger Bypass Valve C Control Circuit Low
- P00BEMass or Volume Air Flow B Circuit Range/Performance - Air Flow Too Low
- P00BFMass or Volume Air Flow B Circuit Range/Performance - Air Flow Too High
- P00C0Turbocharger/Supercharger Bypass Valve B Control Circuit
- P00C2Turbocharger/Supercharger Bypass Valve B Control Circuit High
- P00C3Turbocharger/Supercharger Bypass Valve B Control Circuit Range/Performance
- P00C4Turbocharger/Supercharger Bypass Valve B - Mechanical
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.