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Home >> Saturn >> 2003 >> Ion 1 Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Diagnostic Procedures >> Fuel Systems >> Fuel Pump Electrical Circuit Diagnosis >> Diagnostic Procedure
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Diagnostic Procedure

  1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, go to DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L ION article.
  2. Turn ignition switch to RUN position, engine OFF. Command the fuel pump relay ON and OFF using a scan tool. Repeat the commands as necessary. Does the fuel pump turn ON and OFF? If yes, see INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 2.2L ION article.
  3. Command the fuel pump relay ON and OFF using a scan tool. Do you hear the fuel pump relay click when you command the fuel pump relay ON and OFF? If yes, go to step  9 . If no, go to next step.
  4. Turn ignition switch to OFF position. Remove the fuel pump relay. Turn ignition switch to RUN position, engine OFF. Probe the fuel pump relay control circuit using a test light connected to a good ground. Command the fuel pump relay ON and OFF using a scan tool. Does the test light turn ON and OFF? If yes, go to next step. If no, go to step  6 .
  5. Connect a test light between the fuel pump relay control circuit and the fuel pump relay ground circuit. Command the fuel pump relay ON and OFF using a scan tool. Does the test light turn ON and OFF? If yes, go to step  21 . If no, go to step  24 .
  6. Does the test light remain illuminated with each command? If yes, go to next step. If no, go to step  8 .
  7. Test the fuel pump relay control circuit for a short to voltage. Did you find and correct the condition? If yes, go to step  29 . If no, go to step  28 .
  8. Test the fuel pump relay control circuit for a short to ground or an open. Did you find and correct the condition? If yes, go to step  29 . If no, go to step  22 .
  9. Turn ignition switch to RUN position, engine OFF. Does the fuel pump operate continuously? If yes, go to next step. If no, go to step  11 .
  10. Turn ignition switch to OFF position. Remove the fuel pump relay. Turn ignition switch to RUN position, engine OFF. Does the fuel pump operate continuously? If yes, go to step  23 . If no, go to step  27 .
  11. Inspect the fuel pump fuse. Is the fuel pump fuse open? If yes, go to next step. If no, go to step  15 .
  12. Disconnect the fuel sender harness from the body pass-through connector. Test the fuel pump supply voltage circuit for a short to ground between the fuel pump relay and the body pass-through connector. Replace the fuel pump fuse if necessary. Did you find and correct the condition? If yes, go to step  29 . If no, go to next step.
  13. Lower the fuel tank. Inspect the fuel sender harness on top of the fuel tank for any damage to the harness and a short to ground in the fuel pump supply voltage circuit. Replace the fuel pump fuse if necessary. Did you find and correct the condition? If yes, go to step  29 . If no, go to next step.
  14. Connect all disconnected electrical components. Install a new fuel pump fuse. Command the fuel pump relay ON using a scan tool. Inspect the fuel pump fuse. Is the fuel pump fuse open? If yes, go to next step. If no, go to INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 2.2L ION article.
  15. Turn ignition switch to OFF position. Remove the fuel pump relay. Turn ignition switch to RUN position, engine OFF. Probe the fuel pump relay battery voltage circuit, switch side, using a test light connected to a good ground. Does the test light illuminate? If yes, go to next step. If no, go to step  25 .
  16. Connect a 15-amp fused jumper wire between the fuel pump relay battery voltage circuit and the fuel pump supply voltage circuit. Does the fuel pump operate? If yes, go to step  21 . If no, go to next step.
  17. Disconnect the fuel sender harness from the body pass-through connector. Test the fuel pump supply voltage circuit for an open or high resistance between the fuel pump relay and the body pass-through connector. Did you find and correct the condition? If yes, go to step  29 . If no, go to next step.
  18. Test the ground circuit of the fuel pump for an open or high resistance between the body pass-through connector and ground. Inspect the ground circuit for proper torque, corrosion on the terminals, or damage to the wiring harness. Did you find and correct the condition? If yes, go to step  29 . If no, go to next step.
  19. Test for an intermittent and for a poor connection at the fuel sender harness to the body pass-through connector. Did you find and correct the condition? If yes, go to step  29 . If no, go to next step.
  20. Lower the fuel tank. Inspect the fuel sender harness on top of the fuel tank for a damaged harness and an open circuit. Did you find and correct the condition? If yes, go to step  29 . If no, go to step  26 .
  21. Test for an intermittent and for a poor connection at the fuel pump relay. Did you find and correct the condition? If yes, go to step  29 . If no, go to step  27 .
  22. Test for an intermittent and for a poor connection at the Engine Control Module (ECM). Did you find and correct the condition? If yes, go to step  29 . If no, go to step  28 .
  23. Repair the short to voltage in the fuel pump supply voltage circuit. After repair, go to step  29 .
  24. Repair the open or high resistance in the fuel pump relay ground circuit. After repair, go to step  29 .
  25. Repair the open in the fuel pump relay battery voltage circuit. After repair, go to step  29 .
  26. Inspect for poor connections at the fuel pump, within the fuel tank, before replacing the fuel pump. Replace the fuel sender. Replace the fuel pump fuse if necessary. After repair, go to step  29 .
  27. Replace the fuel pump relay. After repair, go to step  29 .
  28. Replace the ECM. Perform ECM relearn procedure. See ENGINE CONTROL MODULE REPROGRAMMING under PROGRAMMING in SELF-DIAGNOSTICS - 2.2L ION article. After repair, go to next step.
  29. Operate the system to verify the repair. Did you correct the condition? If yes, system is okay at this time. If no, go to step  2 .
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