Lighting System Headlight (Hi-Beam) Circuit

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

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

PERFORM ACTIVE TEST BY INTELLIGENT TESTER

INSPECT FUSE (H-LP UPR)

CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 2 RELAY BLOCK - BATTERY)

CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 2 RELAY BLOCK - BODY GROUND)

LIGHTING SYSTEM - Headlight (HI-BEAM) Circuit


DESCRIPTION

The front controller receives headlight HI switch information from the combination switch, and turns on the headlights.
Bi-function:
This function is activated by a HI beam turn ON signal from the front controller and activates the headlight solenoid built into the headlight unit to slide the shade down.
When the LO beam headlight is switched on, the upper illumination area of the discharge bulb is blocked by the shade and only the lower illumination area is used. When the HI beam is turned on, the headlight solenoid slides the shade down to allow use of the upper illumination area, thus increasing the illumination area and improving visibility when the HI beam is on.

Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System Headlight (Hi-Beam) Circuit


WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System Headlight (Hi-Beam) Circuit


INSPECTION PROCEDURE

1.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 below in the ACTIVE TEST and then check the headlight operation.

    ACTIVE TEST: Body No. 5 (Front Controller)
    Item
    		Test Details
    		Diagnostic Note
    Light Head (High)
    		Headlight (High) ON / OFF
    		-
    OK:
    Headlight assembly illuminates.


NG
Go to step 2
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

2.INSPECT FUSE (H-LP UPR)

  1. Remove the H-LP UPR fuse from the engine room No. 2 relay block.

  1. Measure the resistance of the fuse.

    Standard resistance:
    Below 1 Ω


NG
REPLACE FUSE
OK


3.CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 2 RELAY BLOCK - BATTERY)


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System Headlight (Hi-Beam) Circuit

  1. Disconnect the 2E relay block connector.

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

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    2E-2 - Body ground
    		Always
    		10 to 14 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 2 RELAY BLOCK - BODY GROUND)


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System Headlight (Hi-Beam) Circuit

  1. Check the wire harness between the headlight (LH) and engine room No. 2 relay block, and the headlight (LH) and body ground.

    1. Disconnect the 2G relay block connector.

    2. Disconnect the B12 headlight (LH) connector.

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

      Standard resistance:
      Tester Connection
      		Condition
      		Specified Condition
      2G-13 - B12-2 (HI)
      		Always
      		Below 1 Ω
      2G-13 or B12-2 (HI) - Body ground
      		Always
      		10 kΩ or higher
      B12-1 (E) - Body ground
      		Always
      		Below 1 Ω


    Lexus Is250, Is220D. Gse20 Ale20.Lighting.Lighting System.Lighting System Headlight (Hi-Beam) Circuit

  1. Check the wire harness between the headlight (RH) and engine room No. 2 relay block, and the headlight (RH) and body ground.

    1. Disconnect the 2G relay block connector.

    2. Disconnect the B2 headlight (RH) connector.

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

      Standard resistance:
      Tester Connection
      		Condition
      		Specified Condition
      2G-12 - B2-2 (HI)
      		Always
      		Below 1 Ω
      2G-12 or B2-2 (HI) - Body ground
      		Always
      		10 kΩ or higher
      B2-1 (E) - Body ground
      		Always
      		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ENGINE ROOM NO. 2 R/B (FRONT CONTROLLER)