What it means
The Turbocharger/Supercharger Boost Sensor C circuit signal is above the expected threshold. This indicates a high circuit condition but does not prove the sensor is open or shorted to a particular reference.
At a glance
- Usually lights the check-engine light
How it works
This code concerns the signal circuit for turbocharger or supercharger boost sensor C. The module detects a signal above its expected threshold; an open sensor element, a wire shorted to the 5 V reference, or poor connector contact can produce this high reading.
Common causes
Most likely first.
- Open sensor element
- Signal wire shorted to the 5 V reference
- Connector pins corroded - high contact resistance
Symptoms
- Check engine light on
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
How to diagnose it
- Record freeze-frame data and inspect live data for boost sensor C to see whether the high signal is constant or changes with engine operation.
- Inspect sensor C's connector for corrosion or loose pins and look for a broken wire or damaged insulation that could let the signal contact the 5 V reference.
- Check any fitted sensing hose and port for damage or blockage that could cause readings inconsistent with actual boost.
- Test sensor C's power, ground, and signal circuits for an open sensor element or a short to the 5 V reference using the manufacturer's procedure.
- If the harness and connector pass, test sensor C against the manufacturer's specification and verify its signal after any repair.
Common fixes
- Clean and secure poor connections at the sensor C connector.
- Repair wiring that is open or shorted to the 5 V reference.
- Repair a damaged or blocked sensing hose or port, if fitted.
- Replace boost sensor C if its element is open or its output fails the specified test.
Can I keep driving?
The fault may cause reduced or unpredictable boost, so avoid hard acceleration and overtaking that depends on full power. Stop if there is severe power loss, heavy smoke, or a new intake hiss or whistle.
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.