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 first turned to ON, 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

A01VHANE01

CAUTION / NOTICE / HINT

Note


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

  • Perform electronic throttle learning after replacing the ECM Click here.

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
    A
  2. CHECK WHETHER MIL TURNS OFF


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the tester on.

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

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

      Result
      Result Proceed to
      NO DTC detected A
      Any DTCs detected B

      Tech Tips

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


    B
    A
  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.

    OK
    NG
  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
      F1-11 (CHK) or A71-5 (W) - Body ground Always 10 kΩ or higher

    OK
    NG
  5. CHECK THAT MIL IS ILLUMINATED


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

      OK
      MIL is illuminated.

    OK
    NG
  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
    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
      F1-11 (CHK) - A71-5 (W) Always Below 1 Ω

    OK
    NG