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MIL Circuit Troubleshooting

MIL Circuit Troubleshooting

1. Turn the ignition switch to ON (II).
2. Do the gauge 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 symptom/indication goes away with a known-good gauge control module, replace the original gauge control module.

3. Connect the HDS to the DLC.
4. Check the SCS in the DATA LIST with the HDS.

Is a short indicated?

YES - Go to step 5.

NO - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.

5. Turn the ignition switch to LOCK (0).
6. Disconnect ECM/PCM connector A (49P), then disconnect the HDS.
7. Check for continuity between ECM/PCM connector terminal A32 and body ground.






Is there continuity?

YES - Repair short in the wire between the ECM/PCM (A32) and the DLC.

NO - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.