MIL Does Not Light or MIL Dims At Ignition Switch ON Leaving Engine OFF (But Engine Can Be Starting)

MIL Does Not Light or MIL Dims at Ignition Switch ON Leaving Engine OFF (But Engine Can be Starting)

Wiring Diagram:

Wiring Diagram

Circuit Description
When the ignition switch is turned ON, ECM causes the main relay to turn ON (close the contact point). Then, ECM being supplied with the main power, turns ON the malfunction indicator lamp (MIL). When the engine starts to run and no malfunction is detected in the system, MIL goes OFF but if a malfunction was or is detected, MIL remains ON even when the engine is running.

Step 1- 6:

Troubleshooting