Fuel and air

P0463 — Fuel Level Sensor Circuit High Input

Severity: low Safe to drive

What P0463 means

P0463 sets when the signal voltage from the fuel level sensor in the tank is above the expected range. The sensor is usually a float arm with a variable resistor, and the PCM and instrument cluster read its voltage to work out how much fuel is left. A high signal most often points to an open circuit, a lost ground or a failed sender.

Symptoms

  • Check Engine light is on
  • Fuel gauge stuck on full or empty
  • Erratic or jumping fuel gauge
  • Unexpected low fuel warnings
  • EVAP monitor won't complete
  • Wrong range or fuel remaining readout

Possible causes

  1. Failed fuel level sensor (float and resistor) in the fuel pump module
  2. Open signal wire or poor contact in the harness
  3. Corroded or loose sensor ground
  4. Unplugged or damaged fuel pump module connector
  5. Signal wire shorted to power
  6. Faulty instrument cluster (uncommon)
  7. PCM input circuit failure (rare)

How to diagnose

  1. Scan for codes and view live data for fuel level voltage or percentage, then compare it with the actual fuel amount.
  2. Check for other codes related to the fuel level circuit or fuel pump module.
  3. Inspect the fuel pump module connector under the rear seat, in the trunk or at the tank for corrosion, moisture or a loose fit.
  4. Check the wiring from the tank to the PCM and cluster for opens, chafing and shorts to power.
  5. Test the sensor ground: resistance between the ground pin and body should be near zero.
  6. Unplug the sensor and ground the signal wire per the wiring diagram. The reading should drop to minimum; if not, suspect wiring or the cluster.
  7. Measure sensor resistance with a multimeter as the float moves and compare it to spec.
  8. If wiring and ground are good, test the instrument cluster and PCM.

Common fixes

  • Repair damaged wiring and connectors
  • Clean and tighten ground connections
  • Replace the fuel level sensor or the whole fuel pump module
  • Repair or replace the instrument cluster if it is the cause

Questions and answers

Can I drive with a P0463 code?

Yes, it is usually safe because the engine runs normally. The gauge may be wrong, so refuel based on miles driven rather than the needle.

Why is my fuel gauge stuck on full?

A high signal voltage often comes from an open circuit or a lost sensor ground, which makes the system read the tank as full. Start with the connector and ground at the fuel pump module.

Will P0463 cause an emissions test failure?

A lit Check Engine light and incomplete monitors such as EVAP can fail an inspection where testing is required. After the repair, clear the code and let the monitors complete.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.