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Vehicle Runs Out Of Fuel At 1/2 Full & Rear Tank Is Full At All Times (Dual Tanks)

  1. Disconnect secondary fuel pump connector. Connect a fused jumper wire between secondary fuel pump terminal "A" (Black wire) and ground. See WIRING DIAGRAMS . Connect another fused jumper wire between secondary fuel pump terminal "B" (Light Green wire) and battery voltage. If secondary fuel pump operates, go to next step. If secondary fuel pump does not operate, replace secondary fuel pump.
  2. Connect a test light between secondary fuel pump connector terminal "A" (Black wire) and ground. See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Black wire between secondary fuel pump and ground connection.
  3. Remove fuel pump balance relay located on fuel pump balance module, inside left frame rail. Connect a test light between fuel pump balance relay socket terminal No. 87 (Light Green wire) and secondary fuel pump connector terminal "B" (Light Green wire). See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Light Green wire between fuel pump relay socket and secondary fuel pump.
  4. Connect test light between fuel pump balance relay socket terminal No. 30 (Pink wire) and ground. See WIRING DIAGRAMS . Turn ignition on. If test light illuminates, go to next step. If test light does not illuminate, repair open in Pink wire between fuel pump balance relay socket and underhood fuse/relay center located on rear of left inner fender panel.
  5. Remove fuel pump relay from underhood fuse/relay center located on rear of left inner fender panel. Connect a test light between fuel pump relay socket terminal A3 (Gray wire) and fuel pump balance relay socket terminal No. 85 (Gray wire). See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Gray wire between fuel pump relay socket and fuel pump balance relay socket.
  6. Disconnect fuel pump balance module connector. Connect a test light between fuel pump balance relay socket terminal No. 86 (Light Green wire) and fuel pump balance module connector (connector C1 on gasoline) terminal "D" (Light Green wire). See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Light Green wire between fuel pump balance relay socket and fuel pump balance module.
  7. Reinstall fuel pump balance relay. Connect a fused jumper wire between fuel pump balance module connector (connector C1 on gasoline) terminal "D" (Light Green wire) and ground. See WIRING DIAGRAMS . Connect a test light between secondary fuel pump connector terminal "B" (Light Green wire) and ground. Turn ignition on. Circuit will be energized for about 2 seconds. If test light illuminates, go to next step. If test light does not illuminate, replace fuel pump balance relay.
  8. 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, go to next step. If test light does not illuminate, repair open in Pink wire between fuel pump balance module and splice S315 located in taillight extension harness, near fuel pump balance module breakout.
  9. Connect a test light between fuel pump balance module connector (connector C1 on gasoline) terminal "E" (Black/White wire) and ground. See WIRING DIAGRAMS . If test light illuminates, replace fuel pump balance module. If test light does not illuminate, repair open in Black/White wire between fuel pump balance module and ground connection.
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