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DTC P0463: Fuel Level Sending Unit Volts Too High: Testing

  1. Turn ignition on, with engine off. Using scan tool, read FUEL LEVEL SENSOR voltage. If voltage is more than 9.9 volts, go to next step. If voltage is 9.9 volts or less, go to step  6 .
  2. Turn ignition off. Disconnect fuel pump module connector. Fuel pump module is mounted in top of fuel tank. Inspect connector for damaged pins, corrosion and loose terminals. Repair connector as necessary. If connector is okay, connect a jumper wire between Light Blue/Yellow wire and Black/Light Blue wire at fuel pump module connector. Turn ignition on, with engine off. Using scan tool, read FUEL LEVEL SENSOR voltage. If voltage is one volt or more, go to next step. If voltage is less than one volt, replace fuel level sensor. Fuel level sensor is located on fuel pump module and can be replaced separately. See FUEL LEVEL SENSOR under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION article.
  3. Turn ignition off. Disconnect PCM connectors. PCM is located on firewall in right rear corner of engine compartment. Inspect connectors for damaged pins, corrosion and loose terminals. Repair connectors as necessary. If connectors are okay, measure resistance of Black/Light Blue wire between fuel pump module connector and terminal No. 4 at PCM C1. See Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Black/Light Blue wire between fuel pump module and PCM.
  4. Measure resistance of Light Blue/Yellow wire between fuel pump module connector and terminal No. 26 at PCM C3. See Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Light Blue/Yellow wire between fuel pump module and PCM.
  5. At this time, PCM is assumed to be defective. Replace PCM.
  6. Visually inspect related connectors and wiring harness for damage. Repair connectors and wiring harness as necessary. If connectors and wiring harness are okay, no problem is indicated at this time. Turn ignition on, with engine off. Using scan tool, monitor FUEL LEVEL SENSOR voltage while wiggling fuel pump module connector and wiring harness. Fuel pump module is mounted in top of fuel tank. If voltage changes while wiggling wiring harness, repair wiring harness where wiggling caused voltage to change. If voltage does not change while wiggling wiring harness, no problem is indicated at this time. Test is complete.
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