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, 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 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

B000H3QE01

INSPECTION PROCEDURE

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.

    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 are output 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. B000NMNE09
      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 that the MIL is not illuminated.

      OK
      MIL is not illuminated.

    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 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
      A25-30 (W) or I17-12 (CHK) - 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 should be illuminated.

    NG

    CHECK THAT ENGINE STARTS Click here

    OK

    CHECK FOR INTERMITTENT PROBLEMS Click here

  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 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 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
      A25-30 (W) - I17-12 (CHK) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here