P2B71
Turbocharger/Supercharger A Temperature Sensor Range/Performance
The ECM detects a range/performance fault on the turbocharger/supercharger a temperature sensor. Reading cannot be used reliably for control.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: easy
Symptoms
- Check engine light on
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
Common causes
Ordered by how often each turns out to be the cause.
- Sensor characteristic driftedCommon
- Sensor mounting displacedPossible
- Sensor element aged beyond calibration windowLess likely
Parts involved
- Turbocharger A Temperature Sensor
- Wiring Harness
- ECM
P2B71 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.