P0463Fuel Level Sensor A Circuit High
- 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
- The fuel level sensor is a float on a resistor track in the tank unit. It is no emission part, but other monitors depend on it – the EVAP leak tests, for example, need at least 15 % fuel – so CARB requires it to be monitored and the usual exemption from the warning lamp does not apply. Low and high refer to the signal, not the fuel level: on GM a full tank is about 40 Ω and a low voltage, while Ford judges the resistance directly. P0463 means the signal is above its upper limit: GM above 60 % of the 5 V reference (100 of 125 samples, MIL after two trips), Saab 9-4X above 4.7 V for 5 s, Ford a resistance above 200 Ω for 30 s. Typical is an open circuit – the pull-up then drives the signal high – a short to positive, or an interrupted resistor track. The gauge sticks at one end and a substitute value is used.
- What you may notice
- Fuel gauge wrong, stuck or jumping
- Range display and low-fuel warning wrong
- Check engine light (depending on the maker)
- Likely causes
- LikelySignal or ground wire open, or tank unit connector off
- LikelyResistor track interrupted or worn (sulphur deposits, wiper lifting)
- PossibleCorroded connector or pushed-back pin
- RareSignal wire shorted to positive
- 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 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.