Lighting System Shift Illumination Circuit

Body Electrical. Lexus Is250, Is220D. Gse20 Ale20
Lighting. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK PERSONAL LIGHT (OPERATION)

PERFORM ACTIVE TEST BY INTELLIGENT TESTER

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B)

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B)

CHECK HARNESS AND CONNECTOR (POWER SOURCE)

LIGHTING SYSTEM - Shift Illumination Circuit


DESCRIPTION

The turning on and off of the shift illumination is controlled by the main body ECU LH based on various signals received through BEAN communication.
The main body ECU LH includes a MOS-FET (Metal Oxide Semiconductor - Field Effect Transistor) circuit that fades the shift illumination in and out by duty control.
This MOS-FET circuit has an overheat protection function as a fail-safe. If the main body ECU LH becomes excessively hot, the shift illumination turns off and remains off.
Normal operation will resume when the conditions required to turn on the shift illumination are met again.

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System Shift Illumination Circuit


INSPECTION PROCEDURE

1.CHECK PERSONAL LIGHT (OPERATION)
HINT:
The personal lights and shift illumination share the same power source circuit. Therefore, if none of them come on, inspect the power source circuit first.

  1. Push the switches for the personal lights.

  1. Check that the personal lights come on.

    OK:
    Personal lights come on.


NG
Go to step 5
OK


2.PERFORM ACTIVE TEST BY INTELLIGENT TESTER

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

  1. Turn the intelligent tester main switch on.

  1. Select the item(s) below in the ACTIVE TEST, and check the operation.

    ACTIVE TEST: Body No. 3 (Main Body ECU LH)
    Item
    		Test Details
    		Diagnostic Note
    Shift Light Operation
    		Shift illumination ON / OFF
    		-
    OK:
    The shift illumination comes on.


NG
Go to step 3
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

3.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B)


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System Shift Illumination Circuit

  1. Disconnect the Q1 main body ECU LH connector.

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

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    Q1-3 (RCTY) - Body ground
    		Always
    		10 to 14 V


NG
Go to step 4
OK

REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)

4.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - OVERHEAD J/B)


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System Shift Illumination Circuit

  1. Disconnect the Q1 main body ECU LH connector.

  1. Disconnect the R5 overhead J/B connector

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

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    Q1-3 (RCTY) - R5-14 (SHFT)
    		Always
    		Below 1 Ω
    Q1-3 (RCTY) - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE OVERHEAD J/B

5.CHECK HARNESS AND CONNECTOR (POWER SOURCE)


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System Shift Illumination Circuit

  1. Disconnect the R5 overhead J/B connector

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

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    R5-1 (+B1) - Body ground
    		Always
    		10 to 14 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE OVERHEAD J/B