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Fuel Gauge Indicates Empty At All Times (Dual Tanks)

  1. Disconnect fuel pump balance module connector. Turn ignition on. If fuel gauge indicates empty, go to next step. If fuel gauge indicates above empty, go to step 3).
  2. Disconnect instrument cluster connector. Connect test light between instrument cluster connector terminal No. 16 (Purple wire) and ground. See Figure. See WIRING DIAGRAMS . If test light does not illuminate, replace instrument cluster. If test light illuminates, repair short to ground in Purple wire between instrument cluster and fuel pump balance module.
  3. Disconnect secondary fuel gauge sender connector. Connect a test light between fuel pump balance module connector (connector C1 on gasoline) terminal "B" (Light Blue wire) and ground. See WIRING DIAGRAMS . If test light does not illuminate, go to next step. If test light illuminates, repair short to ground in Light Blue wire between fuel pump balance module and secondary fuel gauge sender.
  4. Connect a test light between fuel pump balance module connector (connector C1 on gasoline) terminal "B" (Light Blue wire) and secondary fuel gauge sender connector terminal "D" (Light Blue wire). See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Light Blue wire between fuel pump balance module and secondary fuel gauge sender.
  5. Connect a test light between secondary fuel gauge sender connector terminal "A" (Black/White wire) and ground. See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Black/White wire between secondary fuel gauge sender and ground connection.
  6. Connect an ohmmeter between secondary fuel gauge sender terminals "A" (Black/White wire) and "D" (Light Blue wire). If resistance is 100 ohms or less, go to next step. If resistance is greater than 100 ohms, replace secondary fuel gauge sender.
  7. Reconnect secondary fuel gauge sender connector. Disconnect fuel pump/sender connector (gasoline) or fuel gauge sender connector (diesel). Connect a test light between fuel pump balance module connector (connector C1 on gasoline) terminal "C" (Dark Blue/White wire) and ground. See WIRING DIAGRAMS . If test light does not illuminate, go to next step. If test light illuminates, repair short to ground in Dark Blue/White wire between fuel pump balance module and fuel pump/sender (gasoline), or fuel gauge sender (diesel).
  8. Connect a test light between fuel pump balance module connector (connector C1 on gasoline) terminal "C" (Dark Blue/White wire) 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. See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Dark Blue/White wire between fuel pump balance module and fuel pump/sender (gasoline), or fuel gauge sender (diesel).
  9. Connect a test light between ground and fuel pump/sender connector terminal "D" (Black/White wire) on gasoline, or fuel gauge sender connector terminal "A" (Black/White wire) on diesel. See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Black/White wire between ground connection and fuel pump/sender (gasoline), or fuel gauge sender (diesel).
  10. Connect an ohmmeter between fuel pump/sender terminals "A" (Dark Blue/White wire) and "D" (Black/White wire) on gasoline, or fuel gauge sender terminals "B" (Dark Blue/White wire) and "A" (Black/White wire) on diesel. If resistance is 100 ohms or less, go to next step. If resistance is greater than 100 ohms, replace fuel pump/sender (gasoline) or fuel gauge sender (diesel).
  11. Connect a test light between fuel pump balance module connector (connector C1 on gasoline) terminal "A" (Pink wire) and ground. See WIRING DIAGRAMS . If test light illuminates, replace fuel pump balance module. If test light does not illuminate, repair open in Pink wire between fuel pump balance module and underhood fuse/relay center located on rear of left inner fender panel.
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