MIL Circuit Troubleshooting

WARNING: This page is about a different car, the 2009 Acura MDX, 2008 Acura MDX, and 2007 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.

Turn the ignition switch ON (II).
Do the gauge self-diagnostic function (see SELF-DIAGNOSTIC FUNCTION ).
Does the MIL indicator flash?

YES - Go to step 3.

NO - Substitute a known-good gauge control module, and recheck. If the MIL circuit is OK, replace the original gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).
Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
Check the SCS in the DATA LIST with the HDS.
Is a short indicated?

YES - Go to step 5.

NO - Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).
Turn the ignition switch OFF.
Disconnect PCM connector A (49P), then disconnect the HDS.
Check for continuity between PCM connector terminal A32 and body ground.

Fig 1: Identifying Continuity Between PCM Connector Terminal A32 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Repair short in the wire between the PCM (A32) and the SRS unit, the DLC.

NO - Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).