SFI SYSTEM > MIL Circuit

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DESCRIPTION

The MIL (Malfunction Indicator Lamp) is used to indicate vehicle malfunctions detected by the ECM. When the ignition switch is turned to the ON position, 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 the ON position, the MIL should be illuminated and should then turn off. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the intelligent tester.

WIRING DIAGRAM


A138550E01


INSPECTION PROCEDURE

1.CHECK THAT MIL IS ILLUMINATED
  1. Perform troubleshooting in accordance with the table below.

    Result:
    Condition
    Proceed to
    MIL remains ON
    A
    MIL does not illuminate
    B


B
Go to step 5
A


2.CHECK WHETHER MIL TURNS OFF
  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to the ON position and turn the tester ON.

  1. Select the following menu items: Powertrain / Engine / DTC.

  1. Check if any DTCs have been stored. Note down any DTCs.

  1. Clear the DTCs (Click here).

  1. Check if the MIL goes off.

    Standard:
    MIL goes off.


OK
REPAIR CIRCUITS INDICATED BY OUTPUT DTCS
NG


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


    A115671E44
  1. Disconnect the A24 (RHD) or A55 (LHD) ECM connector.

  1. Turn the ignition switch to the ON position.

  1. Check that the MIL is not illuminated.

    OK:
    MIL is not illuminated.
  1. Reconnect the ECM connector.



OK
REPLACE ECM (Click here)
NG


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


    A132305E03
  1. Disconnect the A24 (RHD) or A55 (LHD) ECM connector.

  1. Disconnect the F2 combination meter connector.

  1. Measure the resistance.

    Standard resistance (Check for short):
    RHD:
    Tester Connection
    Specified Condition
    W (A24-24) or CHK (F2-4) - Body ground
    10 kΩ or higher
    LHD:
    Tester Connection
    Specified Condition
    W (A55-24) or CHK (F2-4) - Body ground
    10 kΩ or higher
  1. Reconnect the ECM connector.

  1. Reconnect the combination meter connector.



OK
REPAIR OR REPLACE COMBINATION METER ASSEMBLY
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 the ON position.

    OK:
    MIL is illuminated.


OK
SYSTEM OK
NG


6.CHECK THAT ENGINE STARTS
  1. Turn the ignition switch to the ON position.

  1. Start the engine.

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

    HINT:
    *: The intelligent tester cannot communicate with the ECM.


B
GO TO VC OUTPUT CIRCUIT (Click here)
A


7.INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT)
  1. Check the MIL circuit (Click here).



NG
REPAIR OR REPLACE COMBINATION METER ASSEMBLY
OK

CHECK AND REPLACE HARNESS AND CONNECTOR (COMBINATION METER - ECM)