ECD SYSTEM MIL Circuit

DESCRIPTION

The MIL (Malfunction Indicator Lamp) is used to indicate vehicle malfunctions detected by the ECM. When the engine switch is turned to on (IG), power is supplied to the MIL circuit, and the ECM provides the circuit ground which illuminates the MIL.

The MIL operation can be checked visually: When the engine switch is turned to on (IG), the MIL should be illuminated and should turn off after engine is started. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the GTS.

WIRING DIAGRAM

A01XGAPE01

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses of circuits related to this system before performing the following inspection procedure.

  • After replacing the ECM, the new ECM needs registration (See page ) and initialization Click here.

PROCEDURE


  1. CHECK THAT MIL IS ILLUMINATED


    1. Turn the engine switch to on (IG).

    2. Check the illumination condition of the MIL.

      Result
      Result Proceed to
      MIL remains on A
      MIL does not illuminate B
      Illuminates → Turns off C

    B

    CHECK THAT ENGINE STARTS Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  2. CHECK WHETHER DTC OUTPUT RECURS


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    5. Check if any DTCs have been detected. Note down any DTCs.

      Result
      Result Proceed to
      DTC is not output A
      Any DTCs is output B

      Tech Tips

      Check for detected DTCs output from other ECUs which relate to the MIL.


    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC

    A

  3. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS)


    1. Disconnect the ECM connector.

    2. Turn the engine switch on (IG).

    3. Check that the MIL is not illuminated.

      Result
      Result Proceed to
      MIL remains on A
      MIL does not illuminate B

    4. Reconnect the ECM connector.


    B

    REPLACE ECM Click here

    A

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)


    1. Disconnect the combination meter assembly connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      G7-7 (CHK) or G184-7 (W) - Body ground Always 10 kΩ or higher

    4. Reconnect the combination meter assembly connector.

    5. Reconnect the ECM connector.


    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  5. CHECK THAT ENGINE STARTS


    1. Turn the engine switch to on (IG).

    2. Start the engine.

      Result
      Result Proceed to
      Engine starts A
      Engine does not start B

    B

    GO TO VC OUTPUT CIRCUIT Click here

    A

  6. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)


    1. Disconnect the combination meter assembly connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      G7-7 (CHK) - G184-7 (W) Always Below 1 Ω

    4. Reconnect the combination meter assembly connector.

    5. Reconnect the ECM connector.


    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR