P2A47Alternative Fuel Tank C Pressure Sensor 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
- P2A47 is not about broken wires: the tank C sensor delivers a voltage inside its window, yet the pressure it reports cannot be true. Plausible tests are a value that stays flat while the engine draws gas from tank C, one that does not rise during filling, or a clear gap to tanks A and B after a long rest, since cylinders on a common fill manifold settle to similar pressure. For scale, the bulletin SMB-169 that New Flyer issued for CNG buses expects the high-pressure gauge to read somewhere from 200 psi to 3,600 psi after refuelling. The cause can also be mechanical, such as a tank C valve that never opens (P2A27) or a closed manual valve. No manufacturer publishes P2A47 or its thresholds; CARB demands rationality monitoring of such inputs. Compare with a calibrated gauge before replacing parts.
- What you may notice
- Check engine light
- Gas level shown does not match refuelling or consumption
- Shorter driving range on gas
- Likely causes
- LikelyTank C sensor drifted or frozen at one value
- PossibleTank C solenoid not opening or manual valve closed
- RareCorroded contacts shifting the signal
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.