PGM-FI System

MIL Circuit Troubleshooting

 11-77  

  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 70. 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.
  • An intermittent short in the wire between the ECM/PCM (E5) and the idle mixture adjuster (IMA) (without TWC).
  1. Turn the ignition switch OFF.
  2. Turn the ignition switch ON (II).

Is the low oil pressure light on?

YES - Go to step 6.

NO - Go to step 4.

  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 5.

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.

  1. Inspect the No. 20 IG1 (40A) fuse in the under-hood fuse/relay box.

Is the fuse OK?

YES - Repair open in the wire between the No. 20 IG (40A) fuse and the gauge assembly. If the wires are OK, test the ignition switch, refer to the '01 Civic Shop Manual on this CD (see page 22-83).

NO - Repair short in the wire between No. 20 IG (40A) fuse and the under-dash fuse/relay box. Also replace the No. 20 IG (40A) fuse.

  1. Try to start the engine.

Does the engine start?

YES - Go to step 7.

NO - Go to step 10.

  1. Turn the ignition switch OFF.