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Fuel Gauge Inaccurate

  1. Disconnect negative battery cable. Remove instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. Disconnect instrument cluster connectors C250 and C251. See Figure and Figure . Reconnect negative battery cable and turn ignition switch to RUN position. Check for battery voltage at cluster connector C250 terminal No. 16 (Red/Yellow wire). If battery voltage is present, go to next step. If battery voltage is not present, repair short or open in circuit No. 640 (Red/Yellow wire) and retest system.
  2. Measure resistance between ground and instrument cluster connector C250 terminal No. 14 (Orange/Yellow wire). If resistance is less than one ohm, go to next step. If resistance is more than one ohm, repair open in circuit No. 563 (Orange/Yellow wire) and retest system.
  3. Turn ignition off. Measure resistance of Yellow/White wire between instrument connector C250 terminal No. 13 and fuel pump module connector. If resistance is less than 5 ohms, reconnect instrument cluster connectors and go to next step. If resistance is more than 5 ohms, repair open in Yellow/White wire and retest system.
  4. Turn ignition off. Disconnect fuel pump module connector and connect Instrument Gauge System Tester (014-R1063) to cluster side of connector. Set tester to 22 ohms. Turn ignition switch on, wait 60 seconds and read fuel gauge. If fuel gauge reads empty, go to step 6). If gauge does not read empty, go to next step.
  5. Turn ignition off. Measure resistance between cluster printed circuit connections and fuel gauge. If resistance is .2 ohm or less through instrument cluster printed circuit, go to next step. If resistance is more than 0.2 ohm through instrument cluster printed circuit, repair or replace instrument cluster printed circuit and retest system. See PRINTED CIRCUIT under REMOVAL & INSTALLATION.
  6. With instrument gauge system tester still connected, ensure ignition switch is in OFF position. Set tester to 145 ohms. Turn ignition on, wait 60 seconds and read fuel gauge. If fuel gauge reads full, go to next step. If gauge does not read full, replace instrument cluster fuel gauge and amplifier. Retest system.
  7. Remove fuel tank from vehicle. See FUEL GAUGE SENDING UNIT under REMOVAL & INSTALLATION. Remove fuel pump module from tank. Inspect fuel tank for distortion or damage. If fuel tank is distorted or damaged, replace fuel tank. Inspect fuel pump module, float and float rod for damage. If not okay, replace fuel pump module and retest system. If fuel tank, fuel pump, float and float rod are okay, go to next step.
  8. With float rod against empty stop, check resistance of circuit No. 29 (Yellow/White wire) between fuel pump module connector and ground. If resistance is 14-18 ohms, go to next step. If resistance is not 14-18 ohms, replace fuel pump module and retest system.
  9. With float rod against full stop, check resistance of circuit No. 29 (Yellow/White wire) between fuel pump module connector and ground. If resistance is 155-165 ohms, go to next step. If resistance is not 155-165 ohms, replace fuel pump module and retest system.
  10. Connect ohmmeter from ground to fuel pump module signal lead. Slowly move float rod from full stop to empty stop. If ohmmeter reading slowly decreases, replace fuel gauge and retest system. If ohmmeter reading does not decrease, replace fuel pump module and retest system.
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