What it means
A third bypass (recirculation or wastegate) valve used in three-stage charging systems is not responding to control commands. Boost balancing across stages can no longer be achieved.
At a glance
- Usually lights the check-engine light
How it works
This code applies to the control circuit for turbocharger or supercharger bypass valve C. In a system that uses a valve designated C, the module detects that the valve circuit is not responding as commanded, which can interfere with boost control.
Common causes
Most likely first.
- Open solenoid coil
- Open or shorted wiring to the valve
Symptoms
- Reduced engine power or boost
- Sluggish acceleration
- Check-engine light may illuminate
How to diagnose it
- Save freeze-frame data and check live data or commanded tests for bypass valve C to see when its response failed.
- Locate valve C using the vehicle's system diagram, then inspect its connector, wiring, vacuum or pressure connections, and nearby hoses for damage or disconnection.
- Check the valve's solenoid coil for an open circuit using the manufacturer's procedure and specification.
- Test the valve C control wiring for opens or shorts and verify the module's command reaches the valve.
- If the circuit tests pass, check whether valve C moves and holds as commanded using the manufacturer's procedure before replacing the valve.
Common fixes
- Reconnect or secure a loose bypass valve C connector or hose.
- Repair open or shorted wiring in the valve C control circuit.
- Replace bypass valve C if its solenoid coil is open or the valve fails to respond.
- Repair a confirmed module-side control fault after checking the valve and wiring.
Can I keep driving?
Reduced boost can make acceleration sluggish, so avoid hard acceleration and leave extra room when joining or overtaking traffic. Stop if power loss becomes severe, the engine behaves abnormally, or smoke or new intake noise appears.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.