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DTC P0462: Fuel Level Sending Unit Volts Too Low: Testing

  1. Turn ignition on, with engine off. Using scan tool, read FUEL LEVEL SENSOR voltage. If voltage is less than .4 volt, go to next step. If voltage is .4 volt or more, 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, turn ignition on, with engine off. Using scan tool, read FUEL LEVEL SENSOR voltage. If voltage is 9.0 volts or less, go to next step. If voltage is more than 9.0 volts, 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 between terminal No. 4 (Black/Light Blue wire) at PCM C1 connector and terminal No. 26 (Light Blue/Yellow wire) at PCM C3 connector. See Figure . If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair Black/Light Blue and Light Blue/Yellow wires are shorted together. Repair wiring as necessary.
  4. Measure resistance between ground and terminal No. 26 (Light Blue/Yellow wire) at PCM C3 connector. If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground in Light Blue/Yellow wire.
  5. At this time, PCM is assumed to be defective. Replace PCM.
  6. Turn ignition off. Visually inspect related connectors and wiring harness for damage. Repair connectors and wiring harness as necessary. If connectors and wiring harness are okay, 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.
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