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No Malfunction Indicator Light (Mil)

  1. Perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK . After performing OBD system check, go to next step.
  2. Attempt to start engine. If engine starts, go to next step. If engine does not start, go to step  6.
  3. Check fuse No. 4 (Gauges). If fuse if faulty, go to step  14. If fuse is okay, go to next step.
  4. Turn ignition on. Using test light connected to ground, probe ignition feed terminal at instrument cluster connector. See WIRING DIAGRAMS article. If test light illuminates, go to next step. If test light does not illuminate, go to step  11.
  5. Turn ignition off. Disconnect Blue PCM harness connector. Turn ignition on. Connect a fused jumper wire between ground and MIL control circuit of PCM harness connector. See WIRING DIAGRAMS article. If MIL illuminates, go to step  9. If MIL does not illuminate, go to step  10.
  6. Check fuses to PCM ignition and battery feed circuit. If fuses are okay, go to next step. If fuse(s) are faulty, go to step  13.
  7. Turn ignition off. Disconnect PCM harness connectors. Turn ignition on. Using test light connected to ground, probe PCM harness connector ignition and battery feed circuits. See WIRING DIAGRAMS article. If test light illuminates on both circuits, go to next step. If test light does not illuminate on both circuits, go to step  12.
  8. Check for faulty or poor PCM ground connections. Repair as necessary. After repairs, go to step  20. If ground connections are okay, go to next step.
  9. Check for poor connection at PCM harness connector. Repair as necessary. After repairs, go to step  20. If connector is okay, go to step  15.
  10. Check for open in MIL control circuit. Repair as necessary. After repairs, go to step  20. If circuit is okay, go to step  16.
  11. Repair open in ignition feed circuit to instrument cluster. After repairs, go to step  20.
  12. Locate and repair open in PCM battery feed or ignition circuit. Repair as necessary. After repairs, go to step  20.
  13. Locate and repair short to ground in PCM ignition feed circuit or PCM battery feed circuit. Repair as necessary. After repairs, go to step  20.
  14. Locate and repair short to ground in instrument cluster ignition feed circuit. After repairs, go to step  20.
  15. Replace PCM. Program PCM using required equipment. After repairs, go to step  20.
  16. Check for poor connection at MIL control circuit to instrument cluster connector. Repair as necessary. After repairs, go to step  20. If circuit is okay, go to next step.
  17. Remove instrument cluster assembly. Inspect MIL bulb. If bulb is okay, go to step  19. If bulb is faulty, go to next step.
  18. Replace MIL bulb. After replacing bulb, go to step  20.
  19. Replace instrument cluster. After repairs, go to next step.
  20. Start engine and operate vehicle under conditions which original symptom was noted. If system does not operate properly, go to step  2. If system operates properly, go to ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK .
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