Lighting System Interior Light Switch Signal Circuit

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

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE OF INTELLIGENT TESTER

INSPECT OVERHEAD J/B

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

INSPECT OVERHEAD J/B

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

INSPECT OVERHEAD J/B

LIGHTING SYSTEM - Interior Light Switch Signal Circuit


DESCRIPTION

The main body ECU RH receives information on the front interior light switch (marked ON/OFF).
The main body ECU LH receives information on the front interior light switch (marked DOOR).
According to the position of each switch, the main body ECU RH controls the turning on and off of the interior lights, and the main body ECU LH controls the illuminated entry system.

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System  Interior Light Switch Signal Circuit


INSPECTION PROCEDURE

1.READ VALUE OF 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 DATA LIST, and read the display on the intelligent tester.

    DATA LIST: Body (Main Body ECU RH)
    Item
    Measurement Item / Display
    (Range)
    Normal Condition
    Diagnostic Note
    Illumination SW
    Front interior light switch (marked ON/OFF) signal/ ON or OFF
    ON: Front interior light switch (marked ON/OFF) is pushed in
    OFF: Front interior light switch (marked ON/OFF) is not pushed in
    -

    DATA LIST: Body No. 3 (Main Body ECU LH)
    Item
    Measurement Item / Display
    (Range)
    Normal Condition
    Diagnostic Note
    Interior Light
    Front interior light switch (marked DOOR) signal/ ON or OFF
    ON: Front interior light switch (marked DOOR) is pushed in
    OFF: Front interior light switch (marked DOOR) is not pushed in
    -
    OK:
    Switch condition can be displayed.

    Result:

    Result
    Proceed to
    Indication for "ILLUMI SW" does not change
    A
    Indication for "INTERIOR LIGHT" does not change
    B
    Indications for both "ILLUMI SW" and "INTERIOR LIGHT" do not change
    C
    OK
    D


A
Go to step 2

B
Go to step 4

C
Go to step 6
D

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

2.INSPECT OVERHEAD J/B


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System  Interior Light Switch Signal Circuit
  1. Remove the overhead J/B.

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

    Standard resistance:
    Tester Connection
    Switch Condition
    Specified Condition
    R5-34 (CILL) - R5-18 (GND3)
    Front interior light switch (marked ON/OFF) is not pushed in
    10 kΩ or higher
    R5-34 (CILL) - R5-18 (GND3)
    Front interior light switch (marked ON/OFF) is pushed in
    Approx. 10 Ω


NG
REPLACE OVERHEAD J/B
OK


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


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System  Interior Light Switch Signal Circuit
  1. Disconnect the R5 overhead J/B connector.

  1. Disconnect the J75 main body ECU RH connector.

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

    Standard resistance:
    Tester Connection
    Condition
    Specified Condition
    R5-34 (CILL) - J75-4 (UL2)
    Always
    Below 1 Ω
    R5-34 (CILL) - Body ground
    Always
    10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

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

4.INSPECT OVERHEAD J/B


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System  Interior Light Switch Signal Circuit
  1. Remove the overhead J/B.

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

    Standard resistance:
    Tester Connection
    Switch Condition
    Specified Condition
    R5-35 (DOOR) - R5-18 (GND3)
    Front interior light switch (marked DOOR) is not pushed in
    10 kΩ or higher
    R5-35 (DOOR) - R5-18 (GND3)
    Front interior light switch (marked DOOR) is pushed in
    Approx. 10 Ω


NG
REPLACE OVERHEAD J/B
OK


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


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System  Interior Light Switch Signal Circuit
  1. Disconnect the R5 overhead J/B connector.

  1. Disconnect the Q3 main body ECU LH connector.

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

    Standard resistance:
    Tester Connection
    Condition
    Specified Condition
    R5-35 (DOOR) - Q3-11 (BDCY)
    Always
    Below 1 Ω
    R5-35 (DOOR) - Body ground
    Always
    10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

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

6.INSPECT OVERHEAD J/B


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System  Interior Light Switch Signal Circuit
  1. Remove the overhead J/B.

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

    Standard resistance:
    Tester Connection
    Switch Condition
    Specified Condition
    R5-35 (DOOR) - R5-18 (GND3)
    Front interior light switch (marked DOOR) is not pushed in
    10 kΩ or higher
    R5-35 (DOOR) - R5-18 (GND3)
    Front interior light switch (marked DOOR) is pushed in
    Approx. 10 Ω
    R5-34 (CILL) - R5-18 (GND3)
    Front interior light switch (marked ON/OFF) is not pushed in
    10 kΩ or higher
    R5-34 (CILL) - R5-18 (GND3)
    Front interior light switch (marked ON/OFF) is pushed in
    Approx. 10 Ω


NG
REPLACE OVERHEAD J/B
OK

REPAIR OR REPLACE HARNESS OR CONNECTOR (OVERHEAD J/B GROUND CIRCUIT)