P2B7BEVAP System Pressure Sensor/Switch C Circuit Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2B7B means sensor C delivers a signal that is electrically valid but implausible. Mercedes-AMG documents it as P2B7B26 on the GT63 S E Performance (2024–2026): the ME control unit sees the signal change too slowly, caused by interference on the line, and bulletin LI07.70-P-078293 cures it by twisting the sensor leads that run between the engine computer and the EVAP sensors. Audi's V6/V8 bulletin 2069531 lists P2B7B as pressure sensor 3 implausible, but explains that this entry is mislabelled and the test really belongs to P24D6 on sensor G950. VW's 2025–2026 Jetta and Taos set it together with the narrowed G400 orifice. CARB asks for two-sided rationality checks on inputs where feasible. Leak tests may be suspended meanwhile.
- What you may notice
- Check engine light on, no driveability complaint
- EVAP readiness monitor not completing
- Code returns after clearing, often after a few drives
- Likely causes
- LikelyInterference on untwisted sensor wiring (Mercedes-AMG)
- PossibleSensor port or orifice too narrow or blocked
- PossibleFault entry assigned to the wrong sensor (Audi bulletin 2069531)
- RarePressure sensor C drifting or sluggish
- 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: €50 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.