SFI SYSTEM 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 (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 ignition switch is turned to ON (IG), the MIL should be illuminated and should turn off after ignition switch to ON (READY). If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the GTS.

WIRING DIAGRAM

A004FVHE04
A004EK7E02

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. CHECK THAT MIL IS ILLUMINATED


    1. Perform troubleshooting in accordance with the table below.

      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 DTC OUTPUT RECURS


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to 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 detected A
      Any DTCs are detected B

      Tech Tips

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


    B

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

    A

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


    1. A004EK1E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

    2. Turn the ignition switch to ON (IG).

    3. Check that the MIL is not illuminated.

      OK
      MIL is not illuminated.

    OK

    REPLACE ECM Click here

    NG

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


    1. Disconnect the F1 combination meter assembly connector.

    2. Disconnect the A28 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F1-11 (CHK) or A28-27 (W) - Body ground Always 10 kΩ or higher

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  5. CHECK THAT MIL IS ILLUMINATED


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

      OK
      MIL should be illuminated.

    OK

    CHECK FOR INTERMITTENT PROBLEMS Click here

    NG

  6. CHECK THAT ENGINE STARTS


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON (IG).

    3. Turn the GTS on.

    4. Put the engine in inspection mode (maintenance mode) Click here.

    5. 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

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


    1. Disconnect the F1 combination meter assembly connector.

    2. Disconnect the A28 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F1-11 (CHK) - A28-27 (W) Always Below 1 Ω

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR