ECD SYSTEM MIL Circuit

DESCRIPTION

The MIL is used to inform the user when the ECM has detected a vehicle malfunction.

By turning the ignition switch ON, power is supplied to the MIL circuit, and the ECM provides the circuit ground that illuminates the MIL.

Operation of the MIL should be checked visually:

When the ignition switch is first turned ON, the MIL should illuminate. When the engine is started, the MIL should turn off.

WIRING DIAGRAM

A01E0INE01

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK MIL CONDITION

    Tech Tips

    Use the table below to troubleshoot each problem symptom.

    Result
    Condition Proceed to
    MIL remains ON A
    MIL does not illuminate B

    B

    CHECK IF MIL ILLUMINATES Click here

    A

  2. CHECK IF MIL TURNS OFF


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch ON and turn the intelligent tester ON.

    3. Check if DTCs have been stored Click here. If DTCs are present, write them down.

    4. Clear the DTCs using the intelligent tester Click here.

    5. Check that the MIL turns off.

      OK
      The MIL turns off.

    OK

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC

    NG

  3. CHECK WIRE HARNESS (FOR SHORT)

    A01DWKPE04

    1. Disconnect the E20 ECM connector.

    2. Turn the ignition switch ON.

    3. Check that the MIL is not illuminated.

      OK
      The MIL is not illuminated.

    OK

    REPLACE ECM

    NG

  4. CHECK WIRE HARNESS (ECM - COMBINATION METER)

    A01E16ME01

    1. Disconnect the E20 ECM connector.

    2. Disconnect the C8 combination meter connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance
      Tester Connection Specified Condition
      E20-5 (W) - C8-39 Below 1 Ω
      E20-5 (W) or C8-39 - Body ground 10 kΩ or higher

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    NG

    REPLACE COMBINATION METER

  5. CHECK IF MIL ILLUMINATES


    1. Check that the MIL illuminates when turning the ignition switch ON.

      OK
      The MIL illuminates.

    OK

    NORMAL

    NG

  6. INSPECT COMBINATION METER (MIL CIRCUIT)


    1. See the combination meter troubleshooting procedures Click here.


    NG

    REPAIR OR REPLACE COMBINATION METER

    OK

    REPAIR OR REPLACE HARNESS AND CONNECTOR (COMBINATION METER - ECM)