What it means
Voltage on the third bypass valve control line is below the expected window. Usually a short to ground or a shorted solenoid coil.
At a glance
- Usually lights the check-engine light
How it works
This code concerns the control circuit for turbocharger or supercharger bypass valve C. The module detects voltage below the expected range on that circuit, which may result from a control wire shorted to ground, a solenoid coil shorted internally, or poor connector contact.
Common causes
Most likely first.
- Control wire shorted to ground
- Internal short in the solenoid coil
- Connector pins corroded - high contact resistance
Symptoms
- Reduced engine power or boost
- Sluggish acceleration
- Check-engine light may illuminate
How to diagnose it
- Record freeze-frame data and check live data or commanded tests for bypass valve C to see when the low circuit condition occurs.
- Inspect valve C's connector for corrosion or loose pins and trace its control wire for chafing or contact with ground.
- Check the valve C solenoid coil for an internal short using the manufacturer's procedure and specification.
- Test the control circuit for shorts to ground and verify the wiring and terminal contact from the valve to the module.
- If the valve and harness pass, confirm the module's output under the manufacturer's test conditions.
Common fixes
- Clean and secure corroded or loose bypass valve C connector terminals.
- Repair the valve C control wire where it is shorted to ground or damaged.
- Replace bypass valve C if its solenoid coil is internally shorted.
- Repair a confirmed module-side control fault after verifying the valve and harness.
Can I keep driving?
The fault can reduce boost and make acceleration sluggish, so avoid demanding acceleration and allow extra time to merge or overtake. Stop if power loss becomes severe or the engine develops unusual smoke or intake noise.
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.