ECD SYSTEM (w/ DPF) MIL Circuit

DESCRIPTION

The MIL (Malfunction Indicator Lamp) is used to indicate vehicle malfunctions detected by the ECM. When the ignition switch is turned to ON, 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 ignition switch is first turned on (IG), the MIL should be illuminated and should then turn off when the engine is started. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the intelligent tester.

WIRING DIAGRAM

A01KGN4E01

INSPECTION PROCEDURE

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 Click here and initialization Click here.

  • After replacing the fuel supply pump assembly or suction control valve, the ECM needs initialization Click here.

  • After replacing an injector assembly, the ECM needs registration Click here.

PROCEDURE


  1. CHECK THAT MIL IS ILLUMINATED


    1. Check the MIL illumination condition.

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

    B

    CHECK THAT MIL IS ILLUMINATED Click here

    A

  2. CHECK WHETHER MIL TURNS OFF


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

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

    4. Clear DTCs Click here.

    5. Check that the MIL turns off.

      OK
      MIL turns off.

    NG

    CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS) Click here

    OK

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

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


    1. Disconnect the ECM connector.

    2. Turn the ignition switch to ON.

    3. Check that the MIL is not illuminated.

      OK
      MIL is not illuminated.

    4. Reconnect the ECM connector.


    NG

    CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM) Click here

    OK

    REPLACE ECM Click here

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


    1. Disconnect the ECM connector.

    2. Disconnect the combination meter assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      C14-23 - E17-19 (W) Always Below 1 Ω
      C14-23 or E17-19 (W) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

  5. CHECK THAT MIL IS ILLUMINATED


    1. Check if the MIL is illuminated when the ignition switch is turned to ON.

      OK
      MIL is illuminated.

    NG

    CHECK THAT ENGINE STARTS Click here

    OK

    END

  6. CHECK THAT ENGINE STARTS


    1. Turn the ignition switch to ON.

    2. Start the engine.

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

      Tech Tips

      *: The intelligent tester cannot communicate with the ECM.


    B

    GO TO VC OUTPUT CIRCUIT Click here

    A

  7. INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT)


    1. Refer to the combination meter troubleshooting procedure Click here.


    NG

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

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here