LIGHTING SYSTEM LO-beam Headlight does not Illuminate

WIRING DIAGRAM

A000UYZE01

CAUTION / NOTICE / HINT

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.

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. A000UNNE01
      *1 Front view of wire harness connector: (to Multiplex Network Front Light ECU)
      *2 HEAD
      *3 Front view of wire harness connector: (to Windshield Wiper Switch)

      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.

    OK

    END (WINDSHIELD WIPER SWITCH WAS DEFECTIVE)

    NG

    REPLACE MULTIPLEX NETWORK FRONT LIGHT ECU

  5. INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY


    1. Remove the headlight dimmer switch Click here.

    2. Inspect the headlight dimmer switch Click here.


    OK

    REPLACE WINDSHIELD WIPER SWITCH Click here

    NG

    REPLACE HEADLIGHT DIMMER SWITCH ASSEMBLY Click here

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


    1. A000VSHE01
      *1 Front view of wire harness connector: (to Multiplex Network Front Light ECU)

      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

    OK

    REPLACE MULTIPLEX NETWORK FRONT LIGHT ECU

    NG

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

    A000WFUE02
    *1 Front View of wire harness connector: (to Engine Room No. 2 Relay Block)
    *2 Front View of wire harness connector: (to Front Controller)

    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

    A000U7FE01
    *1 Component with harness connected: (Engine Room No. 2 Relay Block)

    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

    OK

    REPLACE ENGINE ROOM NO. 2 RELAY BLOCK

    NG

  9. INSPECT ENGINE ROOM NO. 2 RELAY BLOCK

    A000W4ZE02
    *1 Component without harness connected: (Engine Room No. 2 Relay Block)

    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

    OK

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

    NG

    REPLACE ENGINE ROOM NO. 2 RELAY BLOCK