P2B90
Turbocharger/Supercharger B Temperature Sensor Circuit Low
The ECM detects a circuit low fault on the turbocharger/supercharger b 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.
- Signal wire shorted to groundCommon
- Internal sensor shortPossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Turbocharger B Temperature Sensor
- Wiring Harness
- ECM
P2B90 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.