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A-1, Mil Inoperative

  1. If Malfunction Indicator Light (MIL) does not illuminate with ignition on and with engine off, attempt to start engine. If engine starts, go to step 3). If engine does not start, check fusible links at battery and PCM fuse. If fusible links or PCM fuse are blown, repair short to ground.
  2. If fusible links and PCM fuse are okay, turn ignition on and check power circuits to PCM, including keep alive memory and ignition feed. See appropriate wiring diagram in WIRING DIAGRAMS section for power terminal identification. If power is not available to power terminals of PCM, check for opens in power circuits. If power is available to PCM power terminals, check for poor PCM ground circuits, or replace faulty PCM.
  3. If engine starts and MIL does not illuminate, turn ignition off. Disconnect PCM connectors. Turn ignition on and jumper PCM light driver terminal to ground using a test light. See appropriate wiring diagram in WIRING DIAGRAMS section for power terminal identification.
  4. If MIL is now on, repair light driver terminal connections at PCM or replace faulty PCM. If MIL stays off when test light is used to ground light driver terminal, check for blown instrument panel fuse, faulty bulb, open in light driver circuit between PCM and bulb, driver circuit shorted to voltage, or an open in ignition feed to MIL.
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