P0240Turbocharger/Supercharger Boost Sensor B Circuit Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Boost sensor B is a second boost pressure sensor, for a second turbo or bank on parallel twin-turbo engines or a second stage on two-stage systems. No manufacturer using sensor B codes was found – GM, Ford and Saab, even on two-stage and twin-turbo engines, use a single boost sensor; the description follows CARB and the documented sensor A codes. P0240 is the plausibility fault of sensor B with an electrically valid signal – as with sensor A, compared with barometric and manifold pressure after a stop and with a model while running. A charge air leak on the side or stage of turbo B is a likely cause.
- What you may notice
- Check engine light on
- Loss of power
- Uneven boost between the turbos
- Likely causes
- LikelyCharge air leak on the side or stage of turbo B
- LikelySensor B dirty or drifting
- PossibleContact resistance in the connector
- RareManifold or barometric sensor faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Easy · Often possible to do yourself.Typical cost: €30 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.