Obdaryn

P0462Fuel Level Sensor A Circuit Low

  • 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. P0462 means the signal is below its lower limit: GM below 10 % of the 5 V reference (100 of 125 samples, MIL after two trips), Saab 9-4X below 0.25 V for 5 s, Ford a resistance below 5 Ω for 30 s. Typical is a signal wire shorted to ground or a shorted sensor. 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 wire shorted to ground (chafed at tank or underbody)
  • PossibleSensor shorted or damaged internally
  • PossibleWater or corrosion in the tank connector
  • RareEvaluating module faulty
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

Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.