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Fuel Gauge Inaccurate (Dual Tanks)

  1. Ensure fuel tank is full. Disconnect instrument cluster connector. Connect a fused jumper wire between instrument cluster connector terminal No. 31 (Black/White wire) and ground. See Figure. See WIRING DIAGRAMS . Connect another fused jumper wire between instrument cluster connector terminal No. 22 (Pink wire) and battery voltage. Connect one Red lead of Gauge Tester (J-33431-B) to instrument cluster connector terminal No. 16 (Purple wire). Connect other Red lead to ground.
  2. Set resistance dial on tester to one ohm. Fuel gauge should indicate empty after a short time. Set resistance dial to 45 ohms. Fuel gauge should indicate 1/2 full after a period of time. Set resistance dial to 90 ohms. Fuel gauge should indicate full after a period of time. If fuel gauge indicates correctly, go to next step. If fuel gauge does not indicate correctly, replace instrument cluster.
  3. Remove tester and fused jumper wires from instrument cluster connector. Reconnect instrument cluster connector. Turn ignition on. Disconnect secondary fuel gauge sender connector. Disconnect fuel pump/sender connector (gasoline) or fuel gauge sender connector (diesel). Connect gauge tester between ground and secondary fuel gauge sender connector terminal "D" (Light Blue wire). See WIRING DIAGRAMS . Go to next step.
  4. Adjust tester to 45 ohms. Connect another gauge tester between ground and fuel pump/sender connector terminal "A" (Dark Blue/White wire) on gasoline, or fuel gauge sender connector terminal "B" (Dark Blue/White wire) on diesel. Adjust tester to 45 ohms. If fuel gauge indicates about 1/2 full, go to next step. If fuel gauge indicates much more or much less than 1/2 full, replace fuel pump balance module.
  5. Ensure rear fuel tank is full. Connect an ohmmeter between secondary fuel gauge sender terminals "A" (Black/White wire) and "D" (Light Blue wire). If 90 ohms or more is present, replace fuel pump/sender (gasoline) or fuel gauge sender (diesel). If less than 90 ohms is present, replace secondary fuel gauge sender.
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