What it means
The turbocharger speed sensor B reading is outside the expected range or does not match the expected operating behavior. The code does not by itself identify the sensor location or prove that the vehicle has a second turbocharger.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Turbocharger speed sensor B provides a signal the engine control module uses to monitor turbocharger speed. This code sets when the reading is outside the expected range or does not follow expected operating behavior, which can result from contamination, loose mounting, sensor wear, or another signal problem; it does not identify the sensor's location or prove a second turbo is fitted.
Common causes
Most likely first.
- Oil-contaminated sensor tip
- Sensor element aged beyond calibration window
- Sensor mounting loose - signal damping
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
- Review freeze-frame and live data for sensor B across engine speeds and loads, noting when its reading departs from expected behavior.
- Inspect sensor B and its connector for oil contamination, loose seating, corrosion, or damage.
- Check the sensor mounting and gap or seating arrangement against the manufacturer's procedure, since looseness can damp the signal.
- Inspect wiring near the turbocharger for heat damage, chafing, opens, or shorts.
- If mounting and wiring are sound, test sensor B and inspect its target or reluctor for damage.
Common fixes
- Clean contamination from the sensor B tip and connector as directed by the manufacturer.
- Secure the sensor at its correct mounting position.
- Repair damaged wiring or connector terminals.
- Replace sensor B if its reading remains outside the expected range with correct mounting and sound wiring.
- Repair a damaged target or reluctor if confirmed during inspection.
Can I keep driving?
The fault can cause incorrect boost control, power loss, or limp mode. Avoid heavy loads and hard acceleration; stop if smoke, unusual turbo noise, or severe loss of power develops.
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.