P2A4EAlternative Fuel Temperature Sensor Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- The counterpart to P2A4D: the gas temperature signal rises above its upper limit. With the usual NTC thermistor fed through a pull-up resistor, that equals an absurdly cold reading, and the most frequent reason is an open circuit, either a broken wire, a loose terminal or a sensor that has gone open inside. A short to a voltage source has the same effect. In TransEco's list the related rail temperature High code is attributed to exactly these causes and handled like the Low case, with a substitute value from the intake air sensor or a forced change to petrol. No manufacturer documents P2A4E publicly. Bridging the two pins at the plug should flip the reading to very hot; if not, the break lies between plug and module.
- What you may notice
- Check engine light
- Live data shows gas temperature at its coldest limit
- Bi-fuel vehicle falls back to petrol
- Likely causes
- LikelyBroken wire or loose terminal in the sensor circuit
- PossibleThermistor open internally
- RareSignal wire shorted to a voltage source
- 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 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.