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Home >> Saturn >> 2003 >> LW200 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Diagnostic Procedures >> Ignition Systems >> Electronic Ignition System >> Diagnostic Procedures
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Diagnostic Procedures

  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 SATURN "L" SERIES article.
  2. Crank engine. Observe the CKP Active Counter on the scan tool. Does the CKP Active Counter increment? If yes, go to next step. If no, go to Crankshaft Position Sensor (CKP) System Diagnosis. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L SATURN "L" SERIES article.
  3. Turn ignition off. Remove fuel pump relay. Remove ignition housing. Install Ignition System Diagnosis Harness (J 36012-A). Install Spark Tester (J 26792) on the cylinder No. 1 spark plug jumper wire. Connect the cylinder No. 4 jumper wire to a good ground. Connect the other jumper wires from the 2-3 ignition coil to the respective cylinders. Observe spark tester. Crank engine. Repeat the procedure for the remaining cylinders. Does the spark tester spark on all cylinders? If yes, go to step  6 . If no, go to next step.
  4. Is the no-spark condition only present on one cylinder? If yes, go to step  17 . If no, go to next step.
  5. Is the no-spark condition only present on companion cylinders No. 1-4 or No. 2-3? If yes, go to step  12 . If no, go to step  8 .
  6. Does the spark tester indicate a bright Blue spark on all cylinders? If yes, go to next step. If no, go to step  17 .
  7. Remove the spark plugs. Examine spark plugs for any abnormal conditions or damage. Are the spark plugs in good condition? If yes, system is okay. If no, go to step  24 .
  8. Turn ignition off. Disconnect the harness connector of the Ignition Control Module (ICM). Turn ignition on, with engine off. Connect a test light from the ignition voltage circuit of the ICM to a good ground. Does the test light illuminate? If yes, go to next step. If no, go to step  20 .
  9. Connect test light from the ignition voltage circuit to the ground circuit of the ICM. Does the test light illuminate? If yes, go to next step. If no, go to step  21 .
  10. Turn ignition off. Remove the fuse that supplies ignition voltage to the ICM. Measure the resistance of the ignition voltage circuit of the ICM from the harness connector of the ICM to the fuse. Is the resistance less than 3 ohms? If yes, go to next step. If no, go to step  22 .
  11. Measure the resistance of the ground circuit of the ICM from the harness connector of the ICM to a good ground. Is the resistance less than 3 ohms? If yes, go to next step. If no, go to step  23 .
    12. NOTE: If using a different test light, the bulb resistance needs to be 4 ohms or less.
  12. Turn ignition off. Remove the ICM from the ignition coil housing. Connect the harness connector of the ICM. Confirm that the interconnect is connected to the ICM. Turn ignition on, with engine off. Connect the Injector Test Light (J 34730-405) from the ignition voltage circuit at the ICM interconnect to good ground. Does the test light illuminate? If yes, go to next step. If no, go to step  18 .
  13. Connect the Injector Test Light between the ignition voltage circuit and control circuit for the inoperative ignition coil. Crank engine. Does the test light flash? If yes, go to step  17 . If no, go to next step.
  14. Leave the Injector Test Light connected between the ignition voltage circuit and control circuit for the inoperative ignition coil. Turn ignition off. Disconnect the harness connector of the ICM. Connect jumper wires from the harness connector of the ICM to the corresponding terminals of the ICM. Using the jumper wires, exchange the IC timing control circuits of the ICM. Crank engine. Does the test light flash? If yes, go to next step. If no, go to step  18 .
  15. Test the IC timing control circuit of the ICM for open, short to voltage, short to ground, or high resistance. Did you find and correct the condition? If yes, go to step  28 . If no, go to next step.
  16. Test the low reference circuit of the ICM for an open or high resistance. Did you find and correct the condition? If yes, go to step  28 . If no, go to step  19 .
  17. Test for shorted terminals or a poor connection at the ignition coil housing. Did you find and correct the condition? If yes, go to step  28 . If no, go to step  25 .
  18. Test for shorted terminals or a poor connection at the ICM. Did you find and correct the condition? If yes, go to step  28 . If no, go to step  26 .
  19. Test for shorted terminals or poor connections at the PCM. Did you find and correct the condition? If yes, go to step  28 . If no, go to step  27 .
  20. Repair open or short to ground in the ignition voltage circuit of the ICM. After repair, go to step  28 .
  21. Repair open in ground circuit of the ICM. After repairs, go to step  28 .
  22. Repair high resistance in the ignition voltage circuit of the ICM. After repairs, go to step  28 .
  23. Repair high resistance in the ground circuit of the ICM. After repairs, go to step  28 .
  24. Replace spark plugs. After replacement, go to step  28 .
  25. Replace ignition coil housing. After replacement, go to step  28 .
  26. Replace ICM. After replacement, go to step  28 .
  27. Replace PCM. After replacement, go to next step.
  28. Turn ignition OFF for 30 seconds. Start engine and operate vehicle. Observe the vehicle performance and driveability. Does the vehicle operate normally? If yes, system is okay. If no, go to step  3 .
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