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Diagnostic Procedures

WARNING: This page is about a different car, the 2003 Pontiac Vibe. 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, perform diagnostic system check - engine controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM.
  2. Does vehicle not start or almost start and then stall immediately? If yes, go to step  10. If no, go to next step.
  3. Does vehicle start and run with MIL illuminated and DTC P0340 set? If yes, go to step  5. If no, go to next step.
  4. Install scan tool. Turn ignition switch to RUN position, engine OFF. Save DTC and freeze frame information. Use scan tool to clear DTCs. Operate vehicle within freeze frame conditions as specified. Did DTC P0340 set? If yes, go to next step. If no, go to DIAGNOSTIC AIDS .
  5. Turn ignition OFF. Disconnect CMP sensor 2-pin harness connector. Measure resistance of CMP sensor with a DMM. Is resistance 835-1400 ohms at 14-122°F (-10 to 50°C) or 1060-1645 ohms at 122-212°F (50-100°C)? If yes, go to next step. If no, go to step  13.
  6. Connect scan tool. Connect DVOM across CMP sensor terminals. Select AC voltage on DVOM. Start engine. Observe AC voltage on the DMM while checking engine speed on scan tool. See TEST DESCRIPTION . Was AC voltage indicated approximately twice the engine speed? If yes, go to next step. If no, go to step  12.
  7. Probe ground circuit of CMP sensor on harness side with a test light connected to battery voltage. Does test light illuminate? If yes, go to next step. If no, go to step  11.
  8. Disconnect PCM White 34-pin harness connector C1. Remove CMP input wire from PCM harness connector C1. Reconnect harness connector C1 to PCM, leaving CMP input wire free to be tested. Connect DMM to CMP input wire and ground. Start engine. Observe AC voltage on DMM while observing engine speed on the scan tool. Is AC voltage indicated approximately twice the engine speed? If yes, go to step  14. If no, go to next step.
  9. Repair open or short in CMP input circuit. After repair, go to step  15.
  10. Check for an open in the CMP and CKP sensor ground circuit between splice SP108 and PCM. Repair as necessary. Did you find and correct a condition? If yes, go to step  15. If no, go to step  14.
  11. Repair open in the CMP sensor ground circuit between the sensor and splice SP108. After repair, go to step  15.
  12. Remove CMP sensor. Visually check CMP sensor signal rotor for the following conditions:
    • A missing or damaged tooth.
    • Any foreign material.
    • Correct installation.
    Repair as necessary. Did you find and correct a condition? If yes, go to step  15. If no, go to next step.
  13. Replace CMP sensor. After repair, go to step  15.
  14. Replace PCM. After repair, go to step  15.
  15. Use scan tool to clear DTCs. Turn ignition switch to OFF position for 30 seconds. Start engine. Operate vehicle within CONDITIONS FOR RUNNING DTC  as specified. Does DTC run and pass? If yes, go to next step. If no, go to step  2.
  16. Using scan tool, observe stored information, CAPTURE INFO. If scan tool displays any undiagnosed DTCs, diagnose affected DTCs. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no other DTCs are displayed, system is okay at this time.
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