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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. Testing and Inspection

Does the MIL flash?
YES - Go to step 3.

NO - Substitute a known-good gauge control module (tach), and recheck. If the MIL circuit is OK, replace the original gauge control module (tach). Gauge Control Module Replacement


3. Connect the HDS to the DLC. Reading and Clearing Diagnostic Trouble Codes

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, ECM/PCM Update or substitute a known-good ECM/PCM, Reading and Clearing Diagnostic Trouble Codes then recheck. If the symptom/indication goes away and the ECM/PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM/PCM was substituted, replace the original ECM/PCM. Service and Repair


5. Turn the ignition switch to LOCK (0).

6. Disconnect ECM/PCM connector A (44P), then disconnect the HDS.

7. Check for continuity between ECM/PCM connector terminal A31 and body ground.

Is there continuity?
YES - Repair short in the wire between the ECM/PCM (A31) and the SRS unit, the EPS control unit, or the DLC.

NO - Update the ECM/PCM if it does not have the latest software, ECM/PCM Update or substitute a known-good ECM/PCM, Reading and Clearing Diagnostic Trouble Codes then recheck. If the symptom/indication goes away and the ECM/PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM/PCM was substituted, replace the original ECM/PCM. Service and Repair