LIGHTING SYSTEM, Diagnostic DTC:B2430, B2431

DTC Code DTC Name
B2430 LED Headlight LH Circuit Malfunction
B2431 LED Headlight RH Circuit Malfunction

DESCRIPTION

The illumination of the low beam headlights is controlled by the main body ECU (multiplex network body ECU). When the headlights are turned on, the main body ECU (multiplex network body ECU) receives a signal from the headlight assembly and detects the illumination condition of the low beam headlights.

DTC No. Detection Item DTC Detection Condition Trouble Area
B2430 LED Headlight LH Circuit Malfunction LED headlight LH circuit malfunction

  • Headlight unit LH

  • Main body ECU (multiplex network body ECU)

  • Harness or connector
B2431 LED Headlight RH Circuit Malfunction LED headlight RH circuit malfunction

  • Headlight unit RH

  • Main body ECU (multiplex network body ECU)

  • Harness or connector

Tech Tips

DTC B2430 and B2431 are not output if 20 seconds have not elapsed since the ignition switch was turned on.

WIRING DIAGRAM

A01V8V5E01

CAUTION / NOTICE / HINT

Note


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

  • If the main body ECU (multiplex network body ECU) is replaced, refer to Registration.

    Click here

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs.

      Click here

      OK
      DTC B2430 or B2431 output does not occur.
      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  3. INSPECT HEADLIGHT RELAY (H-LP)


    1. Remove the headlight relay from the No. 1 engine room relayblock.

    2. Inspect the head light relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE HEADLIGHT RELAY (H-LP)

    OK

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


    1. A01V88HC01
      *a

      Front view of wire harness connector

      (to Headlight Relay)

      Remove the headlight relay from the No. 1 engine room relay block.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      Headlight relay terminal 1 - Body ground Always 11 to 14 V
      Headlight relay terminal 5 - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Remove the headlight relay from the No. 1 engine room relay block.

    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 relay terminal 2 - 3B-37 Always Below 1 Ω
      3B-37 - 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. A01V8KIN01

      for LHD:


      1. 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

    2. for RHD:


      1. 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-15 (HRLY) - 3B-37 Always Below 1 Ω
      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    B

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    C

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    A

  7. CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY [H-LP] - HEADLIGHT UNIT)


    1. Remove the headlight relay from the No. 1 engine room relay block.

    2. Disconnect the A78*1 and A79*2 headlight unit connectors.


      • *1: for LH

      • *2: for RH

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

      Standard Resistance
      for LH
      Tester Connection Condition Specified Condition
      Headlight relay terminal 3 - A78-1 (LO) Always Below 1 Ω
      Headlight relay terminal 3 - Body ground Always 10 kΩ or higher
      for RH
      Tester Connection Condition Specified Condition
      Headlight relay terminal 3 - A79-1 (LO) Always Below 1 Ω
      Headlight relay terminal 3 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (HEADLIGHT UNIT - MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] AND BODY GROUND)


    1. Disconnect the A78*1 or A79*2 headlight unit connector.


      • *1: for LH

      • *2: for RH

    2. Disconnect the G79 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance
      for LH
      Tester Connection Condition Specified Condition
      A78-3 (B) - G79-24 (LLEW) Always Below 1 Ω
      A78-2 (E) - Body ground Always Below 1 Ω
      A78-3 (B) - Body ground Always 10 kΩ or higher
      for RH
      Tester Connection Condition Specified Condition
      A79-3 (B) - G79-21 (RLEW) Always Below 1 Ω
      A79-2 (E) - Body ground Always Below 1 Ω
      A79-3 (B) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK HEADLIGHT UNIT


    1. Temporarily replace the headlight unit with a new or normally functioning one.

      Click here

    2. Check for DTCs.

      Click here

      OK
      DTC B2430 or B2431 output does not occur.
      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    A

    END (HEADLIGHT UNIT WAS DEFECTIVE)

    B

    MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    C

    MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here