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Test Q: Fuel Gauge Inaccurate Or Inoperative

  1. If Instrument Panel Cluster (IPC) system diagnostic system check has been performed, go to next step. If IPC system diagnostic system check has not been performed, perform IPC system diagnostic system check. See INSTRUMENT PANEL CLUSTER SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
    2. NOTE: Using a Digital Volt-Ohmmeter (DVOM), verify signal generator/instrument panel tester resistance settings.
    NOTE: Values in table are approximate values based on information obtained from properly operating vehicles. Actual results may vary slightly.
  2. Turn ignition switch to OFF position. Disconnect fuel sender harness connector through access panel in trunk. Connect Signal Generator/Instrument Panel Tester (J 33431-C) between fuel sender harness connector Black wire and Purple wire terminals. Turn ignition switch to RUN position. Vary signal generator/instrument panel tester resistance from 40-250 ohms. Observe fuel gauge. Compare resistance readings to fuel gauge display. See FUEL LEVEL SPECIFICATIONS  table. If fuel gauge does not display correct fuel level, go to next step. If fuel gauge displays correct fuel level, go to step  4 .
    FUEL LEVEL SPECIFICATIONS

    Fuel Gauge Display Resistance (Ohms)
    "E" 40-60
    1/4 106
    1/2 134
    3/4 160
    "F" 195-250
    3. NOTE: Using a DVOM, verify signal generator/instrument panel tester resistance settings. Turn ignition switch to OFF position momentarily between generator/instrument panel tester resistance settings to quickly update scan tool display.
  3. Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). DLC is located below left side of instrument panel, to right of steering column. See Figure . Turn ignition switch to RUN position. Using scan tool, observe FUEL LEVEL parameter in PCM EVAP data list. Vary signal generator/instrument panel tester resistance from 40-250 ohms. Compare resistance readings to scan tool display. See FUEL LEVEL SPECIFICATIONS  table. If scan tool does not display correct fuel level, go to step  5 . If scan tool displays correct fuel level, go to step  11 .
  4. Check for poor connections at fuel level sender, misaligned fuel level sender and/or a deformed fuel tank. If problem is not found, go to step  7 . If problem is found, repair as necessary. After repair, go to step  13 .
  5. Test Purple wire between fuel sender harness connector and Powertrain Control Module (PCM) Blue harness connector C1 terminal No. 69 for high resistance. See Figure . PCM is located in front left corner of engine compartment, inside air cleaner. If high resistance is not found, go to next step. If high resistance is found, repair as necessary. After repair, go to step  13 .
  6. Test Black wire between fuel sender harness connector and PCM Natural harness connector C2 terminal No. 35 for high resistance. If high resistance is not found, go to step  9 . If high resistance is found, repair as necessary. After repair, go to step  13 .
    7. NOTE: Fuel level sender is an integral part of fuel pump assembly.
  7. Remove fuel level sender. See FUEL PUMP under FUEL SYSTEM in appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. Check for stuck fuel level sensor and for foreign material in fuel tank. If problem is not found, go to next step. If problem is found, repair as necessary. After repair, go to step  13 .
  8. Using DVOM, test resistance across fuel level sender terminals (component side) while moving float arm. If resistance changes smoothly from 40-250 ohms, go to DIAGNOSING INTERMITTENTS  . If resistance does not change smoothly from 40-250 ohms, go to step  10 .
  9. Check for poor connections at PCM harness connector. If poor connections are not found, go to step  12 . If poor connections are found, repair as necessary. After repair, go to step  13 .
  10. Replace fuel level sender. See FUEL PUMP under FUEL SYSTEM in appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. After repair, go to step  13 .
  11. Replace IPC. See INSTRUMENT PANEL CLUSTER  under REMOVAL & INSTALLATION. After repair, go to step  13 .
  12. Replace PCM. See POWERTRAIN CONTROL MODULE  under REMOVAL & INSTALLATION. After repair, go to next step.
  13. Using scan tool, clear DTCs. Operate system to verify repair. If system does not operate properly, go to step  2 . If system operates properly, system is okay.
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