LIGHTING SYSTEM, Diagnostic DTC:B2430, B2431

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

DESCRIPTION

This DTC is output when the low beam headlights and high beam headlights do not illuminate, or a malfunction is detected in the communication between the headlight assembly and the AFS ECU. The multiplex network front light ECU (front controller) illuminates and turns off the low beam headlight via the engine room No. 2 relay block (H-LP LO LH, H-LP LO RH). The multiplex network front light ECU (front controller) detects the state of the headlight dimmer switch from the windshield wiper switch assembly via CAN communication. Additionally, the AFS ECU detects the illumination condition of the low beam headlights.

DTC Code DTC Detection Condition Trouble Area
B2430 LED headlight LH circuit malfunction

  • Headlight assembly LH

  • Headlight light control ECU sub-assembly (for LO/HI beam)

  • Headlight LED unit assembly LH (for LO/HI beam)

  • Multiplex network front light ECU (Front controller)

  • AFS ECU

  • Engine room No. 2 relay block

  • Harness or connector
B2431 LED headlight RH circuit malfunction

  • Headlight assembly RH

  • Headlight light control ECU sub-assembly (for LO/HI beam)

  • Headlight LED unit assembly RH (for LO/HI beam)

  • Multiplex network front light ECU (Front controller)

  • AFS ECU

  • Engine room No. 2 relay block

  • Harness or connector

WIRING DIAGRAM

A001FO7E03
A001EAQE03

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. CHECK HEADLIGHT


    1. Check that the low beam headlights and high beam headlights turns on normally when the headlight dimmer switch is operated.

      OK
      The low beam headlights and high beam headlights turns on normally.

    NG

    PERFORM ACTIVE TEST USING GTS (HEADLIGHT LOW) Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (AFS ECU - HEADLIGHT)

    A0019DEE01

    1. Disconnect the A37 AFS ECU connector.

    2. Disconnect the B1*1 or B11*2 headlight connector.


      • *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
      B1-20 (S) - A37-6 (INL) Always Below 1 Ω
      B1-20 (S) - Body ground Always 10 kΩ or higher
      for RH
      Tester Connection Condition Specified Condition
      B11-20 (S) - A37-7 (INR) Always Below 1 Ω
      B11-20 (S) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT HEADLIGHT ASSEMBLY

    A001EQEE03
    *1 Front view of wire harness connector: (to Headlight Light Control ECU [for LO/HI Beam])
    *2 PO
    *3 Component without harness connected: (Headlight)

    1. Remove the headlight Click here.

    2. Disconnect the headlight light control ECU (for LO/HI beam) connector Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      20 (S) - B-11 (PO) Always Below 1 Ω

    NG

    REPLACE HEADLIGHT ASSEMBLY Click here

    OK

  4. CHECK HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY (FOR LO/HI BEAM)


    1. Temporarily replace the headlight light control ECU (for LO/HI beam) with a new or normally functioning one Click here.

    2. Turn the engine switch on (IG).

    3. Turn on the low beam headlights and high beam headlights by operating the headlight dimmer switch.

    4. Check for DTC Click here.

      OK
      DTC B2430 or B2431 output does not occur

    OK

    END (HEADLIGHT LIGHT CONTROL ECU [FOR LO/HI BEAM] WAS DEFECTIVE)

    NG

    REPLACE AFS ECU Click here

  5. 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
      Low beam headlight illumination condition is switched by Active Test

    NG

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

    OK

  6. READ VALUE USING GTS (HEADLIGHT DIMMER SWITCH)


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

      Combination Switch
      Tester Display Measurement Item/Range 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
      GTS display changes according to the switch operation

    NG

    INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY Click here

    OK

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

    A001FTEE01
    *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)

    1. 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
      A50-8 (HEAD) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK WINDSHIELD WIPER SWITCH


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

    2. Check for DTC Click here.

      OK
      DTC B2430 or B2431 output does not occur

    OK

    END (WINDSHIELD WIPER SWITCH WAS DEFECTIVE)

    NG

    REPLACE MULTIPLEX NETWORK FRONT LIGHT ECU

  9. 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

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

    A001B1EE01
    *1 Front view of wire harness connector: (to Multiplex Network Front Light ECU)

    1. 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

  11. CHECK ENGINE ROOM NO. 2 RELAY BLOCK


    1. Remove the cover labeled A.

      A001E2UE01
      *1 Component with harness connected: (Engine Room No. 2 Relay Block)

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      I-5 - Body ground Headlight dimmer switch HEAD 11 to 14 V
      I-6 - Body ground Headlight dimmer switch HEAD 11 to 14 V

    3. Disconnect the 2A engine room No. 2 relay block connector.

      A0019C8E03
      *1 Component without harness connected: (Engine Room No. 2 Relay Block)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2A-1 - I-5 Always Below 1 Ω
      2A-2 - I-6 Always Below 1 Ω

    NG

    REPLACE ENGINE ROOM NO. 2 RELAY BLOCK

    OK

  12. CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 2 RELAY BLOCK - HEADLIGHT)

    A001CUXE01

    1. Disconnect the 2A engine room No. 2 relay block connector.

    2. Disconnect the B1*1 or B11*2 headlight connector.


      • *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
      2A-2 - B1-17 (LO) Always Below 1 Ω
      B1-16 (E) - Body ground Always Below 1 Ω
      2A-2 - Body ground Always 10 kΩ or higher
      for RH
      Tester Connection Condition Specified Condition
      2A-1 - B11-17 (LO) Always Below 1 Ω
      B11-16 (E) - Body ground Always Below 1 Ω
      2A-1 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  13. INSPECT HEADLIGHT ASSEMBLY

    A001FM0E02
    *1 Front view of wire harness connector: (to Headlight Light Control ECU [for LO/HI Beam])
    *2 Component without harness connected: (Headlight)

    1. Remove the headlight Click here.

    2. Disconnect the headlight light control ECU (for LO/HI beam) connector Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      17 (LO) - A-1 (+B) Always Below 1 Ω
      16 (E) - A-2 (GND) Always Below 1 Ω

    NG

    REPLACE HEADLIGHT ASSEMBLY Click here

    OK

  14. INSPECT HEADLIGHT ASSEMBLY

    A001CM4E03
    *1 Front view of wire harness connector: (to Headlight Light Control ECU [for LO/HI Beam])
    *2 Front view of wire harness connector: (to Headlight LED Unit [for LO/HI Beam])
    *3 Connector color: White
    *4 Connector color: Black

    1. Remove the headlight Click here.

    2. Disconnect the headlight light control ECU (for LO/HI beam) connector Click here.

    3. Disconnect the headlight LED unit (for LO/HI beam) connector Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B-2 (MD2) - C-2 Always Below 1 Ω
      B-3 (LO) - C-1 Always Below 1 Ω
      B-1 (HI) - D-2 Always Below 1 Ω
      B-8 (MD1) - D-1 Always Below 1 Ω

    NG

    REPLACE HEADLIGHT ASSEMBLY Click here

    OK

  15. CHECK HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY (FOR LO/HI BEAM)


    1. Temporarily replace the headlight light control ECU (for LO/HI beam) with a new or normally functioning one Click here.

    2. Turn the engine switch on (IG).

    3. Turn on the low beam headlights and high beam headlights by operating the headlight dimmer switch.

    4. Check for DTC Click here.

      OK
      DTC B2430 or B2431 output does not occur

    OK

    END (HEADLIGHT LIGHT CONTROL ECU [FOR LO/HI BEAM] WAS DEFECTIVE)

    NG

    REPLACE HEADLIGHT LED UNIT (FOR LO/HI BEAM) Click here

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

    A001CP6E01
    *1 Front view of wire harness connector: (to Engine Room No. 2 Relay Block)
    *2 Front view of wire harness connector: (to Multiplex Network Front Light ECU)

    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

  17. CHECK ENGINE ROOM NO. 2 RELAY BLOCK

    A001DSGE01
    *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

  18. INSPECT ENGINE ROOM NO. 2 RELAY BLOCK

    A001E6JE03
    *1 Component without harness connected: (Engine Room No. 2 Relay Block)

    1. Remove the cover labeled A.

    2. Disconnect the 2E 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