LIGHTING SYSTEM Headlight (HI-BEAM) Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) receives headlight dimmer switch information signals and illuminates the high beam headlights.

WIRING DIAGRAM

B002ADPE02
B0029X6E04

CAUTION / NOTICE / HINT

Note


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

  • When replacing the main body ECU (multiplex network body ECU), make sure to replace it with a new one.

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (HEADLIGHT)


    1. Using the GTS, perform the Active Test.

      Click here


      Body Electrical > Main Body > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Head Light Hi Headlight dimmer relay ON or OFF -

      Body Electrical > Main Body > Active Test
      Tester Display
      Head Light Hi
      Result
      Proceed to
      High beam headlights come on
      High beam headlights do not come on

    High beam headlights come on

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) for LHD: REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here
    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) for RHD: REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    High beam headlights do not come on

  2. CHECK VEHICLE TYPE


    1. Check the vehicle type.

      Result
      Proceed to
      w/o Side Marker Light
      w/ Side Marker Light

    w/ Side Marker Light

    INSPECT RUNNING LIGHT RELAY Click here

    w/o Side Marker Light

  3. INSPECT HEADLIGHT DIMMER RELAY (DIMMER)


    1. B0029JIN01

      Remove the headlight dimmer relay from the No. 1 engine room relay block and junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Battery voltage applied between terminals 1 and 2 Below 1 Ω
      3 - 5 Battery voltage not applied between terminals 1 and 2 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE HEADLIGHT DIMMER RELAY (DIMMER)

    OK

  4. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER RELAY [DIMMER] - BATTERY)


    1. B00298JC01
      *a

      Front view of wire harness connector

      (to Headlight Dimmer Relay)

      Remove the headlight dimmer relay from the No. 1 engine room relay block and junction block assembly.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      Headlight dimmer relay terminal 3 - Body ground Always 11 to 14 V
      Headlight dimmer relay terminal 2 - Body ground
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER RELAY [DIMMER] - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Remove the headlight dimmer relay from the No. 1 engine room relay block and junction block assembly.

    2. Disconnect the 3B instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Headlight dimmer relay terminal 1 - 3B-54 Always Below 1 Ω
      3B-54 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. B002A1BN08
      *1 DIM

      Remove the instrument panel junction block assembly.

      for LHD:

      Click here

      for RHD:

      Click here

    2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

      for LHD:

      Click here

      for RHD:

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A-22 (DIM) - 3B-54 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY for LHD: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here
    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY for RHD: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

  7. INSPECT RUNNING LIGHT RELAY


    1. Remove the running light relay from the No. 1 engine room relay block and junction block assembly.

    2. Inspect the running light relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE RUNNING LIGHT RELAY

    OK

  8. CHECK HARNESS AND CONNECTOR (RUNNING LIGHT RELAY - BATTERY AND BODY GROUND)


    1. B0029N0C01
      *a

      Front view of wire harness connector

      (to Running Light Relay)

      Remove the running light relay from the No. 1 engine room relay block and junction block assembly.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      Running light relay terminal 6 (+B) - Body ground Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Running light relay terminal 3 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK HARNESS AND CONNECTOR (RUNNING LIGHT RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Remove the running light relay from the No. 1 engine room relay block and junction block assembly.

    2. Disconnect the 3B instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Running light relay terminal 4 (H) - 3B-54 Always Below 1 Ω
      3B-54 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. B002A1BN08
      *1 DIM

      Remove the instrument panel junction block assembly.

      Click here

    2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A-22 (DIM) - 3B-54 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here