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, ignition switch signal is sent to ECM. The ECM causes the main relay to turn ON. Then, ECM (PCM) being supplied with the main power, turns ON the malfunction indicator lamp. 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 when the engine is running.

Step 1 - 5:

Step 6:

Troubleshooting