SFI SYSTEM MIL Circuit

DESCRIPTION

The MIL (Malfunction Indicator Lamp) is used to indicate the detection of vehicle malfunctions by the ECM. When the engine switch is turned 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 engine switch is first turned on (IG), the MIL turns on and then turns off. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the intelligent tester.

WIRING DIAGRAM

A00DUX1E01

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. Check the MIL illumination condition.

      Result
      Condition 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 engine switch on (IG) and turn the tester on.

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

    4. Check for DTCs. Note down any output DTCs.

    5. Clear DTCs Click here.

      Result
      Result Proceed to
      No DTC output A
      DTCs output B

      Tech Tips

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


    B

    REPAIR CIRCUIT INDICATED BY OUTPUT DTC Click here

    A

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


    1. A00DRWAE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ECM)

      Disconnect the A40 ECM connector.

    2. Turn the engine switch on (IG).

    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 - ECM) Click here

    OK

    REPLACE ECM Click here

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


    1. A00DTS0E39
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Combination Meter)
      *2

      Front view of wire harness connector

      (to ECM)

      Disconnect the D66 combination meter connector.

    2. Disconnect the A40 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A40-24 (W) or D66-29 (EFI) - Body ground Always 10 kΩ or higher

    4. Reconnect the combination meter connector.

    5. Reconnect the ECM connector.


    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 engine switch is turned on (IG).

      OK
      MIL is illuminated.

    NG

    CHECK THAT ENGINE STARTS Click here

    OK

    SYSTEM OK

  6. CHECK THAT ENGINE STARTS


    1. Turn the engine switch on (IG).

    2. Check that the engine starts.

      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. CHECK ECM (TERMINAL VOLTAGE)


    1. A00DRWAE02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ECM)

      Disconnect the A40 ECM connector.

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A40-24 (W) - Body ground Engine switch on (IG) 11 to 14 V

    4. Reconnect the ECM connector.


    NG

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

    OK

    REPLACE ECM Click here

  8. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM)


    1. A00DTS0E39
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Combination Meter)
      *2

      Front view of wire harness connector

      (to ECM)

      Disconnect the D66 combination meter connector.

    2. Disconnect the A40 ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A40-24 (W) or D66-29 (EFI) - Body ground Always Below 1 Ω

    4. Reconnect the combination meter connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here