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Diagnostic Procedures

WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
  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 in SELF-DIAGNOSTICS - 2.2L VUE article.
  2. Turn ignition on, with engine off. Command the fuel pump relay ON and OFF with a scan tool. Repeat the commands as necessary. Does the fuel pump turn ON and OFF? If yes, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 2.2L & 3.0L VUE article. If no, go to next step.
  3. Command the fuel pump relay ON and OFF with 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 off. Remove fuel pump relay, located in underhood fuse/relay block. Turn ignition on, with engine off. Probe the control circuit of the fuel pump relay with a test light connected to a good ground. Command the fuel pump relay ON and OFF with 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 test light between the control circuit of the fuel pump relay and ground circuit of the fuel pump relay. Command the fuel pump relay ON and OFF with 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 control circuit of the fuel pump relay 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 control circuit of the fuel pump relay 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 on, with engine off. Does the fuel pump operate continuously? If yes, go to next step. If no, go to step  11 .
  10. Turn ignition off. Remove fuel pump relay. Turn ignition on, with engine off. Does the fuel pump operate continuously? If yes, go to step  23 . If no, go to step  27 .
  11. Inspect fuel pump fuse. Is fuse open? If yes, go to next step. If no, go to step  15 .
  12. Disconnect in-line harness connector for fuel senders. Test the supply voltage circuit of the fuel pump for a short to ground between fuel pump relay and in-line harness connector. Replace 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 fuel tank. Inspect the fuel sender harness on top of the fuel tank for any damage to the harness, or a short to ground in the supply voltage circuit of the fuel pump. Replace 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 with a scan tool. Inspect fuel pump fuse. Is fuel pump fuse open? If yes, go to step  26 . If no, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 2.2L & 3.0L VUE article.
  15. Turn ignition off. Remove fuel pump relay. Turn ignition on, with engine off. Probe the battery voltage circuit of the fuel pump relay, switch side, with 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 10-amp fused jumper wire between the battery voltage circuit of the fuel pump relay and the supply voltage circuit of the fuel pump. Does the fuel pump operate? If yes, go to step  21 . If no, go to next step.
  17. Disconnect the in-line harness connector for the fuel senders. Test the supply voltage circuit of the fuel pump for an open or high resistance between the fuel pump relay and the in-line harness connector. Did you find and correct the condition? If yes, go to step  29 . If no, go to next step.
  18. Inspect the ground circuit for proper torque, corrosion on the terminals, or damage to the wiring harness. Test the ground circuit of the fuel pump for an open or high resistance between the in-line harness connector and ground. 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 in-line harness connector of the fuel senders. Did you find and correct the condition? If yes, go to step  29 . If no, go to next step.
  20. Lower fuel tank. Inspect fuel sender harness on top of the fuel tank for damaged harness or 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 ECM. Did you find and correct the condition? If yes, go to step  29 . If no, go to step  28 .
  23. Repair short to voltage in the supply voltage circuit of the fuel pump. After repairs, go to step  29 .
  24. Repair open or high resistance in the ground circuit of the fuel pump relay. After repairs, go to step  29 .
  25. Repair open in battery voltage circuit of the fuel pump relay. After repairs, go to step  29 .
  26. Inspect for poor connections at the fuel pump, within the fuel tank, before replacing the fuel pump. Replace the primary fuel tank module. Replace fuel pump fuse, if necessary. After repairs, go to step  29 .
  27. Replace fuel pump relay. After replacing relay, go to step  29 .
  28. Replace ECM. See REMOVAL & INSTALLATION article. After replacing ECM, go to next step.
  29. Operate the system in order to verify the repair. Did you correct the condition? If yes, system is okay. If no, go to step  2 .
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