SFI SYSTEM > MIL Circuit

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DESCRIPTION

The Malfunction Indicator Lamp (MIL) is used to indicate the ECM's detection of a vehicle malfunction.
The instrument panel GAUGE fuse provides the circuit with power and the ECM provides the circuit ground that illuminates the MIL.
MIL operations should be checked visually:
The MIL should be illuminated when the engine switch is turned on (IG). If the MIL is always ON or OFF, use the intelligent tester and follow the procedures below to determine the cause of the problem.
If the ECM detects trouble, the MIL illuminates. At this time, the ECM records a DTC in the memory.

WIRING DIAGRAM


A110025E01


INSPECTION PROCEDURE

HINT:
Troubleshoot each problem symptom in accordance with the chart below.


MIL remains on
Start inspection from step 1
MIL is not illuminated
Start inspection from step 3
1.CLEAR DTC

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG) and turn the tester ON.

  1. Read the DTC.

  1. Clear the DTC.

  1. Check that the MIL is not illuminated.

    OK:
    MIL is not illuminated.



OK
REPAIR CIRCUIT INDICATED BY OUTPUT DTC
NG


2.CHECK WIRE HARNESS (CHECK FOR SHORT IN WIRE HARNESS)
A067404E04

  1. Disconnect the A7 ECM connector.

  1. Turn the engine switch on (IG).

  1. Check that the MIL is not illuminated.

    OK:
    MIL is not illuminated.



OK
REPLACE ECM
NG

REPAIR OR REPLACE HARNESS AND CONNECTOR 

3.CHECK THAT MIL IS ILLUMINATED

  1. Check that the MIL is illuminated when turning the engine switch on (IG).

    OK:
    MIL is illuminated.



OK
SYSTEM OK
NG


4.INSPECT COMBINATION METER (MIL CIRCUIT)

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



NG
REPAIR OR REPLACE BULB OR COMBINATION METER
OK

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