LIGHTING SYSTEM, Diagnostic DTC:B2430, B2431

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

DESCRIPTION

These DTCs are stored when the low beam headlights do not illuminate, or a malfunction is detected in the communication between the headlight assembly and main body ECU (multiplex network body ECU).

DTC No. DTC Detection Condition Trouble Area
B2430 LED headlight LH circuit malfunction

  • Light control ECU LH

  • Headlight unit LH

  • Integration relay

  • Harness or connector

  • Main body ECU (multiplex network body ECU)
B2431 LED headlight RH circuit malfunction

  • Light control ECU RH

  • Headlight unit RH

  • Integration relay

  • Harness or connector

  • Main body ECU (multiplex network body ECU)

WIRING DIAGRAM

A01J9SDE01

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      Result
      Result Proceed to
      Both DTC B2430 and B2431 are not output. A
      Both DTC B2430 and B2431 are output. B
      DTC B2430 or B2431 is output. C

    B

    CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - BATTERY AND BODY GROUND) Click here

    C

    INSPECT HEADLIGHT ASSEMBLY Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

  2. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - BATTERY AND BODY GROUND)


    1. A01J9I3E03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Integration Relay)

      Disconnect the 1H integration relay connector.

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

      Standard Voltage
      Tester Connector Condition Specified Condition
      1H-7 (BATT) - Body ground Always 11 to 14 V
      Standard Resistance
      Tester Connection Condition Specified Condition
      1H-3 (GND2) - Body ground Always Below 1 Ω
    3. A01J9LAE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Integration Relay)

      Disconnect the 1G integration relay connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1G-22 (GND1) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Disconnect the 1G integration relay connector.

    2. Disconnect the 2C 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
      1G-9 (HL4) - 2C-32 Always Below 1 Ω
      1G-9 (HL4) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. A01JAEWE06
      Text in Illustration
      *1

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      Remove the instrument panel junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2C-32 - A-15 (HRLY) Always Below 1 Ω
      2C-32 - Body ground Always 10 kΩ or higher

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    OK

  5. REPLACE INTEGRATION NO.1 RELAY


    1. Temporarily replace the integration relay with a new or normally functioning one Click here.

    2. Check for DTC Click here.

      OK
      DTC B2430 and B2431 are not output.

    NG

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    OK

    END

  6. INSPECT HEADLIGHT ASSEMBLY


    1. A01JA9LE04
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Headlight Assembly LH)
      *2

      Front view of wire harness connector

      (to Headlight Assembly RH)

      Disconnect the A10 or A39 headlight assembly connector.

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

      Standard Voltage
      LH Side (B2430)
      Tester Connection Switch Condition Specified Condition
      A10-3 (LO) - Body ground Light control switch in head position 11 to 14 V
      RH Side (B2431)
      Tester Connection Switch Condition Specified Condition
      A39-3 (LO) - Body ground Light control switch in head position 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - POWER DISTRIBUTOR) Click here

    OK

  7. INSPECT MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)


    1. A01JA9LE06
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Headlight Assembly LH)
      *2

      Front view of wire harness connector

      (to Headlight Assembly RH)

      Disconnect the A10 or A39 headlight assembly connector.

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

      Standard Voltage
      LH Side (B2430)
      Tester Connection Switch Condition Specified Condition
      A10-2 (IN2) - Body ground Power switch on (IG) and light control switch in head position 11 to 14 V
      RH Side (B2431)
      Tester Connection Switch Condition Specified Condition
      A39-2 (IN1) - Body ground Power switch on (IG) and light control switch in head position 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - HEADLIGHT ASSEMBLY) Click here

    OK

  8. CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - BODY GROUND)


    1. A01JA9LE07
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Headlight Assembly LH)
      *2

      Front view of wire harness connector

      (to Headlight Assembly RH)

      Disconnect the A10 or A39 headlight assembly connector.

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

      Standard Resistance
      LH Side (B2430)
      Tester Connection Condition Specified Condition
      A10-1 (E) - Body ground Always Below 1 Ω
      RH Side (B2431)
      Tester Connection Condition Specified Condition
      A39-1 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. REPLACE LIGHT CONTROL ECU


    1. Temporarily replace the headlight control ECU with a new or normally functioning one Click here.

    2. Check for DTC Click here.

      OK
      DTC B2430 or B2431 is not output.

    NG

    REPLACE HEADLIGHT UNIT Click here

    OK

    END

  10. CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - POWER DISTRIBUTOR)


    1. Disconnect the 1G integration relay connector.

    2. Disconnect the A10 or A39 headlight assembly connector.

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

      Standard Resistance
      LH Side (B2430)
      Tester Connection Condition Specified Condition
      1G-2 (HLPL) - A10-3 (LO) Always Below 1 Ω
      1G-2 (HLPL) - Body ground Always 10 kΩ or higher
      RH Side (B2431)
      Tester Connection Condition Specified Condition
      1G-1 (HLPR) - A39-3 (LO) Always Below 1 Ω
      1G-1 (HLPR) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE INTEGRATION NO.1 RELAY Click here

  11. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - HEADLIGHT ASSEMBLY)


    1. Disconnect the L8 main body ECU (multiplex network body ECU) connector.

    2. Disconnect the A10 or A39 headlight assembly connector.

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

      Standard Resistance
      LH Side (B2430)
      Tester Connection Condition Specified Condition
      L8-21 (LLEW) - A10-2 (IN2) Always Below 1 Ω
      L8-21 (LLEW) - Body ground Always 10 kΩ or higher
      RH Side (B2431)
      Tester Connection Condition Specified Condition
      L8-5 (RLEW) - A39-2 (IN1) Always Below 1 Ω
      L8-5 (RLEW) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here