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Mil Inoperative: 3.8L

NOTE: After any repairs are completed, perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK .
  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK . After performing OBD system check, go to next step.
  2. Using scan tool, check for DTCs. If any DTCs are present, diagnose DTCs. See DIAGNOSTIC TESTS in appropriate TESTS W/CODES article. If no DTCs are present, go to next step.
  3. Check fuses for PCM battery and ignition feed circuits. If fuses are okay, go to next step. If fuses are open, go to step  9.
  4. Attempt to start engine. If engine starts, go to next step. If engine does not start, go to NO START DIAGNOSIS in appropriate BASIC DIAGNOSTIC PROCEDURES article.
  5. Turn ignition off. Disconnect PCM harness connectors. Turn ignition on. Using a test light connected to ground, probe ignition feed circuit at PCM harness connector. See appropriate wiring diagram in WIRING DIAGRAMS article. If test light illuminates, go to next step. If test light does not illuminate, go to step  8.
  6. Using a test light connected to ground, probe battery feed circuit at PCM harness connector. See appropriate wiring diagram in WIRING DIAGRAMS article. If test light illuminates, go to next step. If test light does not illuminate, go to step  8.
  7. Check for poor PCM ground or PCM ground connection. Repair as necessary.
  8. Locate and repair open in PCM battery feed or ignition feed circuits. Repair as necessary.
  9. Locate and repair short to ground in PCM battery feed or ignition feed circuits. Repair as necessary.
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