Sfi System Mil Circuit

Engine. Lexus Gs430, Gs300. Uzs190 Grs190
3Gr-Fe Engine Control System. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK WHETHER MIL TURNS OFF

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

CHECK THAT MIL IS ILLUMINATED

INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT)

SFI SYSTEM - MIL Circuit


DESCRIPTION

The MIL (Malfunction Indicator Lamp) is used to indicate malfunction detections by the ECM.
By turning the engine switch 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 on (IG) is first turned to on, 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


Lexus Gs430, Gs300. Uzs190 Grs190.3Gr-Fe Engine Control System.Sfi System.Sfi System Mil Circuit


INSPECTION PROCEDURE

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

MIL remains illuminated
Start inspection from step 1
MIL not illuminated
Start inspection from step 3
1.CHECK WHETHER MIL TURNS OFF

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

  1. Turn the tester ON.

  1. Check whether any DTCs have been stored (Click here). Note them down if necessary.

  1. Clear DTCs (Click here).

  1. Check if the MIL turns off.

    OK:
    MIL should turn off.


OK
REPAIR CIRCUIT INDICATED BY OUTPUT DTC
NG


2.CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS)
Lexus Gs430, Gs300. Uzs190 Grs190.3Gr-Fe Engine Control System.Sfi System.Sfi System Mil Circuit

  1. Disconnect the A7 ECM connector.

  1. Turn the engine switch on (IG).

  1. Check the MIL is not illuminated.

    OK:
    MIL is not illuminated.

  1. Reconnect the ECM connector.



OK
REPLACE ECM
NG

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

3.CHECK THAT MIL IS ILLUMINATED

  1. Check if the MIL is illuminated when the engine switch is turns to on.

    OK:
    MIL should be illuminated.


OK
SYSTEM OK
NG


4.INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT)

  1. See the combination meter troubleshooting procedure on page Click here.



NG
REPAIR OR REPLACE BULB OR COMBINATION METER ASSEMBLY
OK

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