P2B8FTurbocharger/Supercharger B Temperature Sensor Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2B8F is the general circuit fault for temperature sensor B, the second sensor of this kind on a charged engine, often belonging to a second turbocharger. Which spot it watches is left to the manufacturer, and none documents this code publicly. The engine computer sets it when the signal is lost or unusable without clearly sitting below or above its range, for example during short interruptions. Sensors near the exhaust side often use a platinum measuring resistor on a mineral-insulated lead, as Heraeus describes in patent US8328419B2, because ordinary NTC parts reach their limit at about 900 degrees Celsius. CARB 13 CCR 1968.2 (e)(15) requires circuit monitoring of such inputs. Out-of-range codes are P2B90 and P2B91; sensor A has P2B6E.
- What you may notice
- Warning lamp with stored code
- Sensor B value missing or jumping in live data
- Likely causes
- LikelyLoose or heat-damaged connector with intermittent contact
- PossibleWiring chafed or brittle near hot exhaust parts
- PossibleTemperature sensor B failed internally
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €60 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.