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Diagnostic Procedure

WARNING: This page is about a different car, the 2003 Pontiac Sunfire, 2003 Pontiac Grand Am, 2003 Oldsmobile Alero, and 2003 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
  1. Did you perform the appropriate 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 ALERO, CAVALIER, GRAND AM & SUNFIRE article or DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS (ALTERNATIVE FUELS) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.
  2. Crank the engine. Observe the CKP ACTIVE COUNTER on the scan tool. Does the CKP Active Counter increment? If yes, go to step  6. If no, go to next step.
  3. Disconnect the CKP harness connector. Turn ignition switch to RUN position, engine OFF. Connect a DMM to the battery ground and each of the CKP sensor circuits at the CKP sensor harness connector. Does the voltage measure more than 3 volts? If yes, go to next step. If no, go to step  9.
  4. Test each CKP sensor circuit for a short to voltage. Did you find and correct the condition? If yes, go to step  25. If no, go to next step.
  5. Turn ignition switch to OFF position. Retest each CKP sensor circuit for a short to voltage. Did you find and correct the condition? If yes, go to step  25. If no, go to step  23.
  6. Turn ignition switch to OFF position. Remove the fuel pump relay using the Relay Puller Pliers (J 43244), or equivalent. Remove the ignition coil housing assembly. Not grounding the ignition coil housing, may cause erratic spark. Install a jumper wire with clips on both ends from the top of the Ignition Control Module (ICM) to ground. Install the Ignition System Diagnostic Harness (J 36012-A), or equivalent. Install a Spark Tester (J 26792), or equivalent, on the No. 1 spark plug jumper wire. Ground the No. 4 (companion to No. 1) spark plug jumper wire. Crank the engine with the remaining spark plug jumper wires connected. Repeat previous steps by installing the spark tester on No. 4 and grounding No. 1. Do the same for No. 2 and No. 3 spark plug wires making sure the companion wire is grounded. Does the spark tester spark on all cylinders? If yes, go to next step. If no, go to step  11.
  7. Turn ignition switch to OFF position. Check for malfunctioning spark plugs. Did you find and correct the condition? If yes, go to step  25. If no, go to next step.
  8. Inspect for basic engine problems. See appropriate article in ENGINES. Did you find and correct any conditions? If yes, go to step  25. If no, go to DIAGNOSTIC AIDS .
  9. Connect the harness connector to the CKP sensor. Disconnect PCM harness connectors. Measure the resistance between the CKP sensor circuits at the PCM harness connector. Is the resistance 500-900 ohms? If yes, go to step  24. If no, go to next step.
  10. Test the CKP signal circuit and the low CKP reference circuit for an open, high resistance or circuits shorted together. Did you find and correct the condition? If yes, go to step  25. If no, go to step  19.
  11. Turn ignition switch to OFF position. Remove the spark plug jumper wires. 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 primary ignition coil voltage circuit at the ICM interconnect and a good ground. Does the voltage measure near battery voltage? If yes, go to next step. If no, go to step  13.
  12. Remove the inner-connect from the ICM. Connect Ignition Module Tester (J 43298), or equivalent in place of the ignition coils. Turn ignition switch to RUN position, engine OFF. Depress the TEST button while cranking the engine. Observe the tester. Does the appropriate 1-4 and 2-3 LEDs flash ON and OFF as the engine is cranking? If yes, go to step  22. If no, go to step  15.
  13. Turn ignition switch to OFF position. Disconnect the ICM harness connector. Turn ignition switch to RUN position, engine OFF. Using DMM, measure the voltage ICM ignition 1 voltage circuit. Does the voltage measure near 12 volts? If yes, go to step  21. If no, go to next step.
  14. Check the ICM ignition 1 voltage circuit for an open or short to ground. Repair as necessary. After repair, go to step  25.
  15. Turn ignition switch to OFF position. Disconnect the ICM harness connector. Connect a DMM from the affected IC timing control circuit to ground, set the DMM to AC voltage. Crank the engine. Does the voltage measure 0.5-2.0 volts? If yes, go to step  17. If no, go to next step.
  16. Test the affected IC timing control circuit for an open, short to ground, short to voltage or a short between the timing control circuits. Did you find and correct the condition? If yes, go to step  25. If no, go to step  23.
  17. Turn ignition switch to OFF position. Using a test light connected to battery positive voltage, probe the ICM ground circuit. Does the test light illuminate? If yes, go to step  21. If no, go to next step.
  18. Test the ICM ground circuit for an open or a short to voltage. Repair as necessary. After repair, go to step  25.
  19. Inspect for poor connections at the CKP sensor. Did you find and correct the condition? If yes, go to step  25. If no, go to next step.
  20. Replace the CKP sensor. Perform the CKP variation learn procedure. See CKP SYSTEM VARIATION LEARN PROCEDURE under PROGRAMMING in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article. After repair, go to step  25.
  21. Replace the ICM. After repair, go to step  25.
  22. Replace the ignition coil housing. After repair, go to step  25.
  23. Inspect for poor connections at the PCM. Did you find and correct the condition? If yes, go to step  25. If no, go to next step.
  24. Replace PCM. See POWERTRAIN CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in appropriate REMOVAL & INSTALLATION article. Program PCM with correct vehicle software and calibration. See PROGRAMMING in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article. After repairs, go to next step. After repair, go to next step.
  25. 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.
  26. Turn ignition switch to OFF position for 30 seconds. Start the engine and operate the vehicle. Observe the MIL, vehicle performance, and driveability. Does the vehicle operate normally, with no MIL illumination and no stored DTCs? If yes, system is okay at this time. If no, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article or DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.
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