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Home >> Lexus >> 2017 >> IS 300 F Sport >> Repair and Diagnosis >> External Pages >> Different car >> Section 4 (Lighting System (Ext) - Diagnostic Codes & Circuit Tests) >> Lighting System >> DTC B2430: LED Headlight LH Circuit Malfunction; DTC B2431: LED Headlight RH Circuit Malfunction [04/2013 - 10/2016] >> Procedure

DTC B2430: LED Headlight LH Circuit Malfunction; DTC B2431: LED Headlight RH Circuit Malfunction [04/2013 - 10/2016]: Procedure

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  1. CHECK FOR DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [04/2013 - 10/2016]

      Body Electrical > Main Body > Clear DTCs 

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [04/2013 - 10/2016]

      Body Electrical > Main Body > Trouble Codes 

      Result

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

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [04/2013 - 06/2014]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [06/2014 - 08/2015]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 10/2016] 

    Result: 

    See step  6

    Result: 

    See step  2

  2. INSPECT SEMICONDUCTOR PWR INTEGRATION ECU 
    1. Remove the Semiconductor pwr integration ECU from the No. 2 engine room relay block and No. 2 junction block assembly.

      Refer to REMOVAL [04/2013 - ]

    2. Inspect the Semiconductor pwr integration ECU.

      Refer to INSPECTION [04/2013 - ]

      Result

      Semiconductor pwr integration ECU is normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE SEMICONDUCTOR PWR INTEGRATION ECU. Refer to  REMOVAL [04/2013 - ] 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU - BATTERY) 
    1. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      2B-1 (BATT) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the 4C instrument panel junction block assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2D-8 (HLLS) - 4C-29 Always Below 1 Ω
      2D-8 (HLLS) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Remove the instrument panel junction block assembly.

      Refer to REMOVAL [04/2013 - ]

    2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
      GTY470421Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Instrument Panel Junction Block Assembly)
      - -
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4C-29 - MB-15 (HRLY) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [04/2013 - ] 

    Result: 

    NG 

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [04/2013 - ] 

  6. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU - HEADLIGHT ASSEMBLY) 
    1. Disconnect the A34*1 or A2*2 headlight assembly connector.
      1. *1: for LH Side
      2. *2: for RH Side
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      FOR LH SIDE (B2430)

      Tester Connection Condition Specified Condition
      A34-6 (B) - Body ground Engine switch off, light control switch in head position 11 to 14 V
      FOR RH SIDE (B2431)

      Tester Connection Condition Specified Condition
      A2-6 (B) - Body ground Engine switch off, light control switch in head position 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR LH SIDE (B2430)

      Tester Connection Condition Specified Condition
      A34-5 (LO) - Body ground Always Below 1 Ω
      FOR RH SIDE (B2431)

      Tester Connection Condition Specified Condition
      A2-5 (LO) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)) 
    1. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      FOR LH SIDE (B2430)

      Tester Connection Condition Specified Condition
      A34-7 (S) - Body ground Engine switch on (IG), light control switch in head position 11 to 14 V
      FOR RH SIDE (B2431)

      Tester Connection Condition Specified Condition
      A2-7 (S) - Body ground Engine switch on (IG), light control switch in head position 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  9

  9. CHECK LIGHT CONTROL LED ECU 
    1. Temporarily replace the light control LED ECU with a new or known good one.

      Refer to REMOVAL [04/2013 - 10/2016]

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [04/2013 - 10/2016]

      Body Electrical > Main Body > Trouble Codes 

      Result

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

    Result: 

    END 

    Result: 

    See step  10

  10. CHECK HEADLIGHT UNIT 
    1. Temporarily replace the headlight unit with a new or known good one.

      Refer to REMOVAL [04/2013 - 10/2016]

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [04/2013 - 10/2016]

      Body Electrical > Main Body > Trouble Codes 

      Result

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

    Result: 

    END (HEADLIGHT UNIT WAS DEFECTIVE) 

    Result: 

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [04/2013 - ] 

  11. CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)) 
    1. Disconnect the K2 main body ECU (multiplex network body ECU) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR LH SIDE (B2430)

      Tester Connection Condition Specified Condition
      A34-7 (S) - K2-16 (LLEW) Always Below 1 Ω
      A34-7 (S) - Body ground Always 10 kΩ or higher
      FOR RH SIDE (B2431)

      Tester Connection Condition Specified Condition
      A2-7 (S) - K2-3 (RLEW) Always Below 1 Ω
      A2-7 (S) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [04/2013 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  12. INSPECT SEMICONDUCTOR PWR INTEGRATION ECU 
    1. Remove the Semiconductor pwr integration ECU from the No. 2 engine room relay block and No. 2 junction block assembly.

      Refer to REMOVAL [04/2013 - ]

    2. Inspect the Semiconductor pwr integration ECU.

      Refer to INSPECTION [04/2013 - ]

      Result

      Semiconductor pwr integration ECU is normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (HEADLIGHT ASSEMBLY - SEMICONDUCTOR PWR INTEGRATION ECU) 

    Result: 

    NG 

    REPLACE SEMICONDUCTOR PWR INTEGRATION ECU. Refer to  REMOVAL [04/2013 - ]