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Test B: Fuel Gauge Inaccurate

  1. Turn ignition off. Disconnect fuel sending unit connector. Connect Instrument Gauge Tester (014-R1063) test leads to fuel sending unit connector Blue/Red wire terminal and ground. Set tester to 160 ohms. Turn ignition on. Turn tester on and wait one minute. Fuel gauge should read full or above. Turn ignition off. Set tester to 15 ohms. Turn ignition on and wait one minute. Fuel gauge should read empty or below. If fuel gauge reads as specified, go to next step. If fuel gauge does not read as specified, go to step  4.
  2. Visually inspect fuel tank for damage or deformation. Replace fuel tank as necessary. Retest system. If fuel tank is okay, go to next step.
  3. Visually inspect fuel pump for damage or connector problems. Inspect float and float rod for damage or float rod obstruction. If fuel pump and wiring is okay, replace fuel sending unit. Retest system. If fuel pump and wiring is damaged, repair as necessary.
  4. Turn ignition off. Measure resistance between ground and fuel sending unit connector Black wire. Resistance should be less than 5 ohms. If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Black wire. Retest system.
  5. Remove instrument cluster. See INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. Disconnect instrument cluster connector C266A. Measure resistance of Blue/Red wire between instrument cluster connector C266A terminal No. 3 and fuel sending unit connector. See Figure. Resistance should be less than 5 ohms. Measure resistance between ground and instrument cluster connector C266A terminal No. 3 (Blue/Red wire). Resistance should be more than 10 k/ohms. If resistance is as specified, go to next step. If resistance is not as specified, repair open or short to ground in Blue/Red wire. Retest system.
  6. Visually inspect instrument cluster printed circuit for damage, cracks or hot spots. Replace instrument cluster printed circuit as necessary and retest system. See PRINTED CIRCUIT  under REMOVAL & INSTALLATION. If printed circuit is okay, replace fuel gauge and fuel indicator module. See FUEL GAUGE  and FUEL INDICATOR MODULE  .
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