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Diagnostic Procedures

  1. Perform diagnostic system check. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 3.4L AZTEK & RENDEZVOUS article. After performing diagnostic system check, go to next step.
  2. Attempt to start the engine. Does engine start and run? If yes, go to next step. If no, go to step  4 .
  3. Disconnect the Crankshaft Position Sensor (CKP) sensor "B" connector from the Ignition Control Module (ICM). ICM control module is located on top of rear valve cover. CKP sensor "B" is located on right side of engine block. See Figure . Measure the resistance from the CKP sensor 1 signal circuit to the low reference circuit of the CKP sensor "B" with a DVOM. See Figure . Is the resistance within 800-1200 ohms? If yes, go to next step. If no, go to step  28 .
  4. Disconnect the CKP sensor "A". CKP sensor "A" is located on front of engine, near crankshaft pulley. See Figure . Observe the 3X crank sensor parameter with a scan tool. Crank the engine. Does the scan tool indicate a 3X crank sensor signal present? If yes, go to next step. If no, go to step  11 .
  5. Reconnect the CKP sensor "A". Test for spark at each cylinder with a Spark Tester (J-26792). Did you observe any non-sparking cylinders? If yes, go to next step. If no, go to step  9 .
  6. Inspect and test the affected cylinder spark plug wires, ignition coils and spark plugs for a short to ground or an arching to ground. If carbon tracking or corrosion is present, replace both components that are affected. Did you find and correct the condition? If yes, go to step  32 . If no, go to next step.
  7. Test the resistance of the spark plug wires. Is resistance more than 3000 ohms per foot? If yes, go to step  30 . If no, go to next step.
  8. Measure the secondary resistance of the ignition coils. Is the resistance 5000-8000 ohms? If yes, go to step  25 . If no, go to step  29 .
  9. Inspect the spark plug wires for proper routing and for the correct firing order. If any spark plug wires are found to be misrouted, reroute as necessary. Did you find and correct the condition? If yes, go to step  32 . If no, go to next step.
  10. Remove spark plugs. Inspect spark plugs. Did you find the problem? If yes, go to step  31 . If no, see DIAGNOSTIC AIDS  .
  11. Connect the CKP sensor "A". Disconnect the IC module. Turn ignition on. Connect a test light between the IC module ignition 1 voltage circuit and a good ground. See Figure . Does the test light illuminate? If yes, go to next step. If no, go to step  24 .
  12. Connect a test light between the IC module ignition 1 voltage circuit and the IC module ground circuit. Does the test light illuminate? If yes, go to next step. If no, go to step  26 .
  13. Test for an intermittent and for a poor connection at the ICM. Did you find and correct the condition? If yes, go to step  32 . If no, go to next step.
  14. Disconnect the CKP sensor "B" connector from the ICM. Probe the CKP sensor 1 signal circuit of the CKP sensor "B" with a test light connected to battery voltage. Does the test light illuminate? If yes, go to step  17 . If no, go to next step.
  15. Probe the CKP sensor 1 signal circuit of the CKP sensor "B" with a test light connected to a good ground. Does the test light illuminate? If yes, go to step  18 . If no, go to next step.
  16. Ensure the battery voltage is within specifications. Measure the voltage from the CKP sensor 1 signal circuit and the low reference circuit of the CKP sensor "B" with DVOM at the ICM harness connector. Crank the engine while observing the AC scale. Is the voltage greater than 200 mV? If yes, go to step  27 . If no, go to step  19 .
  17. Test the CKP sensor 1 signal circuit for a short to ground. Did you find and correct the condition? If yes, go to step  32 . If no, go to step  20 .
  18. Test the CKP sensor 1 signal circuit for a short to ground. Did you find and correct the condition? If yes, go to step  32 . If no, go to step  20 .
  19. Test the CKP sensor "B" circuits for an open or CKP sensor 1 signal and low reference circuit shorted together. Did you find and correct the condition? If yes, go to step  32 . If no, go to next step.
  20. Test for an intermittent and for a poor connection at the ICM. Did you find and correct the condition? If yes, go to step  32 . If no, go to next step.
  21. Test for an intermittent and for a poor connection at the CKP sensor. Did you find and correct the condition? If yes, go to step  32 . If no, go to next step.
  22. Remove CKP sensor. Visually inspect the CKP sensor for physical damage, excessive play or looseness, improper installation, foreign material passing between the CKP sensor and reluctor wheel or wiring routed too closely to secondary ignition components. Did you find and correct the condition? If yes, go to step  32 . If no, go to next step.
  23. Visually inspect the reluctor wheel for foreign material passing between the CKP sensor and reluctor wheel, physical damage, excessive end play or looseness, improper installation, or excessive air gap between CKP sensor and reluctor wheel. Did you find and correct the condition? If yes, go to step  32 . If no, go to step  28 .
  24. Repair the open or the short to ground in the IC module ignition 1 voltage circuit. Replace fuse, if necessary. After repairs, go to step  32 .
  25. Remove the coils associated with the cylinder that did not have spark. Connect a test light across the ignition module primary circuit, between the ICM terminals for the coils. Observe the test light while cranking the engine. Does the test light flash continuously while the engine is being cranked? If yes, go to step  29 . If no, go to step  27 .
  26. Repair open in the IC module ground circuit. After repairs, go to step  32 .
  27. Replace IC module. After replacing module, go to step  32 .
  28. Replace CKP sensor "B". After replacing sensor, go to step  32 .
  29. Replace affected ignition coil(s). After replacing ignition coil(s), go to step  32 .
  30. Replace spark plug wires. After replacing spark plug wires, go to step  32 .
  31. Replace spark plugs. After replacing spark plugs, go to next step.
  32. Turn ignition off for 30 seconds. Start engine and operate vehicle. Observe the MIL, vehicle performance and driveability. Does the vehicle operate normally, with no MIL? If yes, system is okay. If no, go to step  2 .
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