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Home >> Saturn >> 2003 >> L200 Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> System Tests >> Mil Always On >> Diagnostic Procedures
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Diagnostic Procedures

  1. Perform diagnostic system check - engine controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check - engine controls, go to next step.
  2. Turn ignition off. Disconnect PCM harness connectors. Turn ignition switch to RUN position, engine off. Observe the MIL. Is the MIL illuminated? If yes, go to next step. If no, go to step  5.
  3. Check the MIL control circuit for a short to ground. Did you find and correct the condition? If yes, go to step  6. If no, go to next step.
  4. Replace IPC. Go to appropriate INSTRUMENT PANEL article in ACCESSORIES & EQUIPMENT. After replacement, go to step  6.
  5. Replace PCM. See POWERTRAIN CONTROL MODULE in REMOVAL & INSTALLATION - SATURN "L" SERIES article. Perform PCM relearn procedure. See PCM REPROGRAMMING  under PROGRAMMING. After replacing PCM, go to next step.
  6. Turn ignition switch to OFF position for 30 seconds. Start engine. Does the vehicle operate correctly without any unwanted MIL illumination, and without any stored DTCs? If yes, system is okay at this time. If no, go to DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM.
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