What it means
The turbocharger speed sensor B circuit signal is above the expected range. The cause may be in the sensor, wiring, connector, or circuit supply.
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 sends the engine control module a signal used to track turbo speed. This code sets when that signal is above the expected range, which can happen if the signal wire contacts reference voltage or the supply wire contacts battery voltage; it is distinct from a low-signal fault.
Common causes
Most likely first.
- Signal wire shorted to reference voltage
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
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 to confirm the high reading and the conditions when it occurs.
- Inspect sensor B's connector and turbo-area harness for pinched wiring, damaged insulation, corrosion, or loose terminals.
- Check the signal wire for a short to reference voltage and the supply wire for contact with battery voltage, following the manufacturer's procedure.
- Test sensor supply, ground, and signal circuits against the manufacturer's specification.
- If circuit tests pass, test sensor B and inspect its target or reluctor for damage.
Common fixes
- Repair a signal wire shorted to reference voltage.
- Repair a pinched supply wire contacting battery voltage.
- Clean corroded terminals and repair loose or damaged connector pins.
- Replace sensor B if it produces a high signal with sound wiring and correct supply.
Can I keep driving?
A high sensor B signal can disrupt turbo monitoring and boost control, with possible power loss or limp mode. Avoid heavy acceleration and stop if severe power loss, smoke, or unusual turbo noise occurs.
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.