LIGHTING SYSTEM LO-beam Headlight does not Illuminate

WIRING DIAGRAM

A01GIDOE03

INSPECTION PROCEDURE

Note


  • First perform the communication function inspections in HOW TO PROCEED WITH TROUBLESHOOTING to confirm that there are no CAN communication malfunctions before troubleshooting this symptom.

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips

If a discharge headlight bulb's condition cannot be determined through a visual check, replace with a normally functioning bulb or interchange the left and right bulbs and check its condition.

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (HEADLIGHT LOW)


    1. Using the GTS, perform the Active Test Click here.

      Body No. 5
      Tester Display Test Part Control Range
      Head Light Low Low beam headlight illumination operation OFF - ON
      OK
      Condition sign can be displayed.

    NG

    CHECK MULTIPLEX NETWORK FRONT LIGHT ECU (HRLY VOLTAGE) Click here

    OK

  2. READ VALUE USING GTS (HEADLIGHT DIMMER SWITCH)


    1. Using the GTS, read the Data List Click here.

      Combination Switch
      Tester Display Measurement Item/Display Normal Condition Diagnostic Note
      Head Light Switch Headlight dimmer switch signal (HEAD position)/ON or OFF

      ON: Headlight dimmer switch HEAD position

      OFF: Headlight dimmer switch OFF

      		 -
      OK
      Condition sign can be displayed.

    NG

    INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (MULTIPLEX NETWORK FRONT LIGHT ECU - WINDSHIELD WIPER SWITCH)


    1. A01GIW5E03

      Disconnect the A50 multiplex network front light ECU connector.

    2. Disconnect the L25 windshield wiper switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A50-8 (HEAD) - L25-7 (HEAD) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK WINDSHIELD WIPER SWITCH (OPERATION)


    1. Temporarily replace the windshield wiper switch with a new or normally functioning one Click here.

    2. Check that the low beam headlight illuminates.

      OK
      Low beam headlight illuminates.

    NG

    REPLACE MULTIPLEX NETWORK FRONT LIGHT ECU

    OK

    END (WINDSHIELD WIPER SWITCH WAS DEFECTIVE)

  5. INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY


    1. Remove the headlight dimmer switch Click here.

    2. Inspect the headlight dimmer switch Click here.


    NG

    REPLACE HEADLIGHT DIMMER SWITCH ASSEMBLY Click here

    OK

    REPLACE WINDSHIELD WIPER SWITCH Click here

  6. CHECK MULTIPLEX NETWORK FRONT LIGHT ECU (HRLY VOLTAGE)


    1. A01GLPSE15

      Disconnect the A50 multiplex network front light ECU connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A50-7 (HRLY) - Body ground Always 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (MULTIPLEX NETWORK FRONT LIGHT ECU - ENGINE ROOM NO. 2 RELAY BLOCK) Click here

    OK

    REPLACE MULTIPLEX NETWORK FRONT LIGHT ECU

  7. CHECK HARNESS AND CONNECTOR (MULTIPLEX NETWORK FRONT LIGHT ECU - ENGINE ROOM NO. 2 RELAY BLOCK)

    A01GKYDE08

    1. Disconnect the A50 multiplex network front light ECU connector.

    2. Disconnect the 2G engine room NO. 2 relay block connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A50-7 (HRLY) - 2G-6 Always Below 1 Ω
      A50-7 (HRLY) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK ENGINE ROOM NO. 2 RELAY BLOCK

    A01GJN1E08

    1. Remove the cover labeled A.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      I-1 - Body ground Always 11 to 14 V

    NG

    INSPECT ENGINE ROOM NO. 2 RELAY BLOCK Click here

    OK

    REPLACE ENGINE ROOM NO. 2 RELAY BLOCK

  9. INSPECT ENGINE ROOM NO. 2 RELAY BLOCK

    A01GLFCE01

    1. Remove the cover labeled A.

    2. Disconnect the 2E engine room No. 2 relay block connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2E-2 - I-1 Always Below 1 Ω

    NG

    REPLACE ENGINE ROOM NO. 2 RELAY BLOCK

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - ENGINE ROOM NO. 2 RELAY BLOCK)