MIL Remains ON after Engine Starts

MIL Remains ON after Engine Starts

Wiring Diagram

Refer to MIL Does Not Come ON with Ignition Switch in ON Position and Engine Stopped (but Engine Can Be Started) MIL Does Not Come ON with Ignition Switch in ON Position and Engine Stopped (but Engine Can Be Started).

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, transmits indication ON signal of MIL to combination meter in order to turn MIL ON. And then, combination meter turns MIL ON. When the engine starts to run and no malfunction is detected in the system, ECM transmits MIL indication OFF signal to combination meter in order to turn MIL OFF. And then, combination meter turns MIL OFF, but if a malfunction was or is detected, MIL remains ON even when the engine is running.

Troubleshooting

1. DTC check

Start engine and recheck DTC of ECM and TCM while engine running.

Is there any DTC(s)?
YES -
Go to Step 2 of Engine and Emission Control System Check Engine and Emission Control System Check
and Step 2 of CVT System Check CVT System Check.
NO -
Go to Step 2.

2. CAN communication line circuit check

Check CAN communication line circuit between control modules for open, short, high resistance and connections. Initial Inspection and Diagnostic Overview

Is circuit in good condition?
YES -
Substitute a known-good combination meter and recheck. If MIL still remains ON, substitute a known-good ECM and recheck.
NO -
Repair or replace CAN communication circuit.