P2A6BAlternative Fuel Rail Pressure Regulator Inlet Pressure Sensor Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2A6B is stored when the signal voltage of the regulator inlet pressure sensor drops below its valid band. With a typical three-wire transducer (5 V feed, signal, ground) that means a signal lead shorted to ground, a lost 5 V reference or a failed sensor element. A low voltage would read as an almost empty cylinder, so a bi-fuel vehicle may refuse gas mode or show an empty gauge with a full tank; Ford's 2003 bi-fuel CNG logic drove the gauge to empty whenever the sensor built into its regulator failed. GM uses the same reading on the Impala together with tank temperature to work out the fill level. No maker publishes P2A6B directly. Measure feed and signal at the plug with the key on before condemning the sensor.
- What you may notice
- Check engine light on
- Gas gauge shows empty although the tank is full
- Gas mode refused, bi-fuel vehicle runs on petrol
- Likely causes
- LikelySignal wire chafed through and shorted to ground
- Possible5 V reference open or pulled down by another sensor on the same feed
- PossibleInlet pressure transducer internally shorted
- 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: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.