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Home >> Toyota >> 2013 >> Prius Plug-in >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 129 (Lighting System (Diagnostic Codes & Circuit Tests) (Except Plug-In)) >> Lighting System >> DTC B2430: LED Headlight LH Circuit Malfunction; DTC B2431: LED Headlight RH Circuit Malfunction >> Procedure
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DTC B2430: LED Headlight LH Circuit Malfunction; DTC B2431: LED Headlight RH Circuit Malfunction: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK FOR DTC 
    1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    2. Check for DTCs. Refer to DTC CHECK / CLEAR .
      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 → See step   2 

    C → See step   6 

    A → See step   15 

  2. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - BATTERY AND BODY GROUND) 
    1. Disconnect the 1H integration relay connector.
      Fig 1: Identifying Integration Relay Connector Terminals
      GTY225517Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Integration Relay)
    3. Disconnect the 1G integration relay connector.
      Fig 2: Identifying 1G No. 1 Integration Relay Connector
      GTY221746Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Integration Relay)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  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: Go to next step 

  4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Remove the instrument panel junction block assembly.
      Fig 3: Identifying Instrument Panel Junction Block Assembly
      GTY226798Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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
      TEXT IN ILLUSTRATION

      *1 Component without harness connected
      (Instrument Panel Junction Block Assembly)

    NG → REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

    OK: Go to next step 

  5. REPLACE INTEGRATION NO. 1 RELAY 
    1. Temporarily replace the integration relay with a new or normally functioning one. Refer to REMOVAL .
    2. Check for DTC. Refer to DTC CHECK / CLEAR .

      OK

      DTC B2430 and B2431 are not output.

    NG → See step   12 

    OK → END 

  6. INSPECT HEADLIGHT ASSEMBLY 
    1. Disconnect the A10 or A39 headlight assembly connector.
      Fig 4: Identifying A10 And A39 Headlight Assembly Connector Terminals
      GTY236404Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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
      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)

    NG → See step   10 

    OK: Go to next step 

  7. INSPECT MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 
    1. Disconnect the A10 or A39 headlight assembly connector.
      Fig 5: Identifying A10 And A39 Headlight Assembly Connector Terminals
      GTY229663Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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
      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)

    NG → See step   11 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - BODY GROUND) 
    1. Disconnect the A10 or A39 headlight assembly connector.
      Fig 6: Identifying A10 And A39 Headlight Assembly Connector Terminals
      GTY229667Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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
      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)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. REPLACE LIGHT CONTROL ECU 
    1. Temporarily replace the headlight control ECU with a new or normally functioning one. Refer to DISASSEMBLY .
    2. Check for DTC. Refer to DTC CHECK / CLEAR .

      OK

      DTC B2430 or B2431 is not output.

    NG → See step   14 

    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 → See step   13 

  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 → See step   12 

  12. REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL 
  13. REPLACE INTEGRATION NO. 1 RELAY. Refer to  REMOVAL 
  14. REPLACE HEADLIGHT UNIT. Refer to  REMOVAL 
  15. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
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