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Home >> Saturn >> 2003 >> Ion 1 Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Diagnostic Procedures >> Ignition System >> Electronic Ignition System 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. Attempt to start the engine. Does the engine start and run? If yes, go to step  11 . If no, go to next step.
  3. Crank the engine. Observe the CMP Resync Counter parameter using a scan tool. Does the CMP Resync counter increment? If yes, go to step  7 . If no, go to next step.
  4. Turn ignition switch to OFF position. Disconnect the Engine Control Module (ECM). Measure the resistance between the Crankshaft Position (CKP) sensor signal 1 circuit and low reference circuit using a DVOM. Is the resistance 500-900 ohms? If yes, go to step  20 . If no, go to next step.
  5. Test the CKP sensor signal 1 circuit for a short to voltage, an open, high resistance and CKP sensor circuits shorted together. Did you find and correct the condition? If yes, go to step  23 . If no, go to next step.
  6. Test the low reference circuit for an open, high resistance and CKP circuits shorted together. Did you find and correct the condition? If yes, go to step  23 . If no, go to step  12 .
  7. Turn ignition switch to OFF position. Disconnect the Ignition Control Module (ICM) harness connector. Turn ignition switch to RUN position, engine OFF. Measure the voltage between the ignition 1 voltage circuit and the ICM ground circuit. Is the voltage 11-13 volts? If yes, go to step  9 . If no, go to next step.
  8. Measure the voltage between the ignition 1 voltage circuit and a good ground. Is the voltage 11-13 volts? If yes, go to step  17 . If no, go to step  11 .
  9. Turn ignition switch to OFF position. Disconnect the IGN fuse, located in the Underhood Fuse Block. Measure the resistance of the ICM ignition 1 voltage circuit between the Underhood Fuse Block to the ICM. Is the resistance less than 3 ohms? If yes, go to next step. If no, go to step  17 .
  10. Turn ignition switch to OFF position. Connect the ICM. Remove the ICM from the ignition coil housing. Confirm that the interconnect is connected to the ICM module. Turn ignition switch to RUN position, engine OFF. Measure the voltage between the ignition coil voltage circuit at the ICM interconnect and a good ground. Does the voltage measure 11-13 volts? If yes, go to next step. If no, go to step  13 .
  11. Turn ignition switch to OFF position. Remove the ICM from the ignition coil housing. Confirm that the interconnect is connected to the ICM. Connect a test light between battery positive voltage and one of the coil control circuits at the interconnect. Crank the engine. Repeat this test on the other coil control circuit. Does the test light flash on both coil control circuits during cranking? If yes, go to step  22 . If no, go to step  13 .
  12. Test for an intermittent or poor connection at the ECM. Did you find and correct the condition? If yes, go to step  23 . If no, go to step  14 .
  13. Test for an intermittent or poor connection at the harness and interconnect of the ICM. Did you find and correct the condition? If yes, go to step  23 . If no, go to step  21 .
  14. Test for an intermittent or poor connection at the CKP sensor. Did you find and correct the condition? If yes, go to step  23 . If no, go to next step.
  15. Remove the CKP sensor. Inspect the CKP sensor for physical damage or looseness. Did you find and correct the condition? If yes, go to step  23 . If no, go to step  18 .
  16. Inspect the reluctor wheel for physical damage or looseness. Did you find and correct the condition? If yes, go to step  23 . If no, go to step  19 .
  17. Repair the ignition 1 voltage circuit for one of the following conditions:
    • An open.
    • A short to ground.
    • High resistance.

    After repair, go to step  23 .

  18. Repair the open in the ICM ground circuit. After repair, go to step  23 .
  19. Replace the CKP sensor. After repair, go to step  23 .
  20. 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 step  23 .
  21. Replace the ICM. After repair, go to step  23 .
  22. Replace the ignition coil housing. After repair, go to step  23 .
  23. Attempt to start the engine. Does the engine start and continue to run? If yes, go to next step. If no, go to step  2 .
  24. Clear the DTCs using a scan tool. Turn ignition switch to OFF position for 30 seconds. Allow the engine to reach operating temperature. Observe the DTC information using a scan tool. Are there any DTCs that have not been diagnosed? If yes, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ION article. If no, system is okay at this time.
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