PGM-FI System

MIL Circuit Troubleshooting

 11-32  

  1. Turn the ignition switch ON (II) and watch the Malfunction Indicator Lamp (MIL).

Does the MIL come on and stay on?

YES - If the MIL always comes on and stays on, go to step 68. But if the MIL sometimes works normally, first check for these problems.

  • An intermittent short in the wire between the ECM/PCM (E29) and the Data Link Connector (DLC).
  • An intermittent short in the wire between the ECM/PCM (E31) and the gauge assembly.

NO - If the MIL is always off, go to step 2. But if the MIL sometimes works normally, first check for these problems.

  • A loose No. 10 METER (7.5A) fuse in the under-dash fuse/relay box.
  • A loose No. 20 IG (40A) fuse in the under-hood fuse/relay box.
  • A loose No. 6 ECU (ECM/PCM) (15A) fuse in the under-hood fuse/relay box.
  • A loose No. 17 FUEL PUMP (15A) fuse in the under-dash fuse/relay box.
  • A poor connection at ECM/PCM terminal E31.
  • An intermittent open in the GRN/ORN wire between the ECM/PCM (E31) and the gauge assembly.
  • An intermittent short in the wire between the ECM/PCM (A21) and the manifold absolute pressure (MAP) sensor.
  • An intermittent short in the wire between the ECM/PCM (A20) and the throttle position (TP) sensor, knock sensor, exhaust gas recirculation (EGR) valve position sensor.
  • An intermittent short in the wire between the ECM/PCM (A8) and the knock sensor.
  1. Turn the ignition switch OFF.
  2. Press the inertia switch button.
  3. Turn the ignition switch ON (II).

Does the MIL come on for 2 seconds after the ignition switch is turned ON (II)?

YES - Intermittent failure system is OK at this time.

NO - Go to step 5.

  1. Turn the ignition switch OFF.
  1. Disconnect the inertia switch 3P connector.
  2. Connect the inertia switch 3P connector terminals No. 1 and No. 3 with a jumper wire.

INERTIA SWITCH 3P CONNECTOR

Wire side of female terminals

  1. Turn the ignition switch ON (II).

Does the MIL come on for 2 seconds after the ignition switch is turned ON (II)?

YES - Replace the inertia switch.

NO - Go to step 9.

  1. Turn the ignition switch OFF.
  2. Turn the ignition switch ON (II).

Is the low oil pressure light on?

YES - Go to step 13.

NO - Go to step 11.

  1. Inspect the No. 10 METER (7.5 A) fuse in the under-dash fuse/relay box.

Is the fuse OK?

YES - Go to step 12.

NO - Repair short in the wire between No. 10 METER (7.5A) fuse and the gauge assembly. Also replace the No. 10 METER (7.5A) fuse.