SFI SYSTEM MIL Circuit

DESCRIPTION

The MIL (Malfunction Indicator Lamp) is used to indicate vehicle malfunctions detected by the ECM. By turning the ignition switch 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 turned to ON, the MIL should be illuminated and should then turn off. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure. If the ECM detects any trouble, the MIL illuminates. At this time, the ECM records a DTC in the memory.

WIRING DIAGRAM

A01ELAQE16
A01EM1VE08

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK THAT MIL ILLUMINATES


    1. Turn the ignition switch to ON.

    2. Check the illumination of the MIL.

      Result
      Result Proceed to
      MIL remains illuminated (Illuminated at all) A
      MIL remains off (Does not illuminate at all) B
      MIL illuminates, but turns off after engine is started C

    B

    CHECK IF ENGINE STARTS Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  2. CHECK WHETHER MIL TURNS OFF


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

    5. Check if any DTCs have been stored. Note any DTCs.

    6. Clear the DTCs Click here.

    7. Check if the MIL goes off.

      Result
      Result Proceed to
      MIL goes off A
      MIL does not go off B

    B

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

    A

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

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


    1. A01EL4RE62
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

    2. Turn the ignition switch to ON.

    3. Check if the MIL is illuminated.

      Result
      Result Proceed to
      MIL is not illuminated A
      MIL is illuminated B

    B

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

    A

    REPLACE ECM Click here

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


    1. Disconnect the accessory 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
      F2-10 (CHK) or A49-36 (W) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ACCESSORY METER ASSEMBLY Click here

  5. CHECK IF ENGINE STARTS


    1. Start the engine.

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

      Tech Tips

      *: The GTS cannot communicate with the ECM.


    B

    GO TO VC OUTPUT CIRCUIT Click here

    A

  6. CHECK HARNESS AND CONNECTOR (ECM TERMINAL VOLTAGE)


    1. Disconnect the ECM connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A49-36 (W) - Body ground Ignition switch ON 11 to 14 V

    NG

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

    OK

    REPLACE ECM Click here

  7. CHECK HARNESS AND CONNECTOR (ACCESSORY METER ASSEMBLY - ECM)


    1. Disconnect the accessory 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
      F2-10 (CHK) - A49-36 (W) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ACCESSORY METER ASSEMBLY Click here