What it means
The ECM detects a range/performance fault on the turbocharger/supercharger b temperature sensor. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The turbocharger/supercharger B temperature sensor measures temperature for the ECM's engine-control strategy. P2B92 sets when the signal remains electrically plausible but does not track expected temperature behavior, such as when the sensor has drifted or is mounted incorrectly.
Common causes
Most likely first.
- Sensor characteristic drifted
- Sensor mounting displaced
- Sensor element aged beyond calibration window
Symptoms
- Check engine light on
How to diagnose it
- Review freeze-frame data and compare the B sensor reading with other available temperature readings from a cold start through warm-up for a consistent offset or implausible response.
- Inspect the B sensor mounting and confirm it is seated in the intended position, with no looseness or displacement.
- Check the B sensor connector and wiring for corrosion or damage that could distort its signal.
- Compare the sensor's response as temperature changes with the manufacturer's specification and the expected behavior for this sensor.
- If mounting and wiring are sound but the reading remains out of range or responds incorrectly, replace the aged or drifting B sensor.
Common fixes
- Reseat and secure a displaced B temperature sensor.
- Clean or repair corroded terminals or damaged wiring at the B sensor.
- Replace the B temperature sensor if its response has drifted beyond the manufacturer's specification.
Can I keep driving?
If the check-engine light is the only symptom, a short, gentle trip may be possible, but avoid sustained heavy boost until the reading is checked. A drifting B temperature signal may cause the ECM to make less reliable control decisions and can affect emissions.
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.