SFI SYSTEM > MIL Circuit

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DESCRIPTION

The MIL is used to inform the user when the ECM has detected a vehicle malfunction.
By turning the ignition switch ON, power is supplied to the MIL circuit, and the ECM provides the circuit ground that illuminates the MIL.
Operation of the MIL should be checked visually:
When the ignition switch is first turned ON, the MIL should illuminate. When the engine is started, the MIL should turn off.

WIRING DIAGRAM


A115353E02


INSPECTION PROCEDURE

1.CHECK THAT MIL IS ILLUMINATED

  1. Perform troubleshooting in accordance with the chart below.

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


B
Go to step 5
A


2.CHECK IF MIL TURNS OFF

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch ON and turn the intelligent tester ON.

  1. Check if DTCs have been stored (Click here). If DTCs are present, write them down.

  1. Clear the DTCs using the intelligent tester (Click here).

  1. Check that the MIL turns off.

    OK:
    The MIL turns off.


OK
REPAIR CIRCUIT INDICATED BY OUTPUT DTC
NG


3.CHECK WIRE HARNESS (FOR SHORT)
A065744E04

  1. Disconnect the E10 ECM connector.

  1. Turn the ignition switch ON.

  1. Check that the MIL is not illuminated.

    OK:
    The MIL is not illuminated.


OK
REPLACE ECM
NG


4.CHECK WIRE HARNESS (ECM - COMBINATION METER)
G034708E09

  1. Disconnect the E10 ECM connector.

  1. Disconnect the C25 combination meter connector.

  1. Measure the resistance of the wire harness side connectors.

    Standard resistance:
    Tester Connection
    		Specified Condition
    E10-30 (W) - C25-39
    		Below 1 Ω
    E10-30 (W) or C25-39 - Body ground
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK

REPLACE COMBINATION METER ASSEMBLY 

5.CHECK IF MIL ILLUMINATES

  1. Check that the MIL illuminates when turning the ignition switch ON.

    OK:
    The MIL illuminates.


OK
NORMAL
NG


6.CHECK THAT ENGINE STARTS

  1. Turn the ignition switch ON.

  1. Start the engine.

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
A


7.INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT)

  1. See the combination meter troubleshooting procedure (Click here).



NG
REPAIR OR REPLACE BULB OR COMBINATION METER ASSEMBLY
OK

REPAIR OR REPLACE HARNESS AND CONNECTOR (COMBINATION METER - ECM)