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Home >> Toyota >> 2021 >> C-HR LE >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Headlights >> Automatic Headlight Beam Level Control System - Diagnostic Codes >> Automatic Headlight Beam Level Control System >> DTC B2424: Headlight Beam Level Control Motor LH Lost Communication; DTC B2425: Headlight Beam Level Control Motor RH Lost Communication [09/2019 - ] >> Procedure
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DTC B2424: Headlight Beam Level Control Motor LH Lost Communication; DTC B2425: Headlight Beam Level Control Motor RH Lost Communication [09/2019 - ]: Procedure

  1. CLEAR DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / AFS / Clear DTCs.
    5. Clear the DTCs.

      Body Electrical > AFS > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. CHECK FOR DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Wait 10 seconds or more.
    4. Turn the Techstream on.
    5. Enter the following menus: Body Electrical / AFS / Trouble Codes.
    6. Check for DTCs.

      Body Electrical > AFS > Trouble Codes 

      OK

      DTC B2424 and B2425 are not output.

      Result

      Result Proceed to
      OK A
      NG (DTC B2424 is output) B
      NG (DTC B2425 is output) C
      NG (DTC B2424 and B2425 are output) D

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2019 - 08/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2020 - ] 

    Result: 

    C 

    See step  4

    Result: 

    D 

    See step  7

    Result: 

    B 

    See step  3

  3. INSPECT HEADLIGHT ECU SUB-ASSEMBLY LH 
    GTY886198Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *A for TMMT Made *B for TMC Made
    *a Component without harness connected
    (Headlight ECU Sub-assembly LH)    		 - -
    1. Remove the headlight ECU sub-assembly LH.

      Refer to REMOVAL [09/2019 - 08/2020] , or refer to REMOVAL [08/2020 - ]

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A95-20 (LINL) - C-13 (LINLI)*1 Always Below 1 Ω
      A16-20 (LINL) - C-13 (LINLI)*2 Always Below 1 Ω
      1. *1: for TMMT Made
      2. *1: for TMC Made

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE HEADLIGHT UNIT ASSEMBLY LH. Refer to  DISASSEMBLY [09/2019 - 12/2021]  , or refer to  DISASSEMBLY [12/2021 - ] 

    Result: 

    NG 

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH. Refer to  REMOVAL [09/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - ] 

  4. CHECK HARNESS AND CONNECTOR (HEADLIGHT ECU SUB-ASSEMBLY LH - HEADLIGHT ECU SUB-ASSEMBLY RH) 
    1. Disconnect the A95*1 or A16*2 headlight ECU sub-assembly LH connector.
      1. *1: for TMMT Made
      2. *1: for TMC Made
    2. Disconnect the A17 headlight ECU sub-assembly RH connector.
    3. Measure the resistance according to the value(s) in the chart below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A95-20 (LINL) - A17-20 (LINL)*1 Always Below 1 Ω
      A16-20 (LINL) - A17-20 (LINL)*2 Always Below 1 Ω
      1. *1: for TMMT Made
      2. *1: for TMC Made

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HEADLIGHT ECU SUB-ASSEMBLY LH (LINL TERMINAL SIGNAL OUTPUT) 
    GTY885308Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Headlight ECU Sub-assembly RH)
    1. Disconnect the headlight ECU sub-assembly RH connector.
    2. Using the Techstream, check the waveform.

      OK

      Tester Connection Switch Condition Specified Condition
      A17-20 (LINL) - Body ground Engine switch on (IG) Pulse generation

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH. Refer to  REMOVAL [09/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - ] 

    Result: 

    OK 

    See step  6

  6. INSPECT HEADLIGHT ECU SUB-ASSEMBLY RH 
    GTY886207Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component without harness connected
    (Headlight ECU Sub-assembly RH)    		 - -
    1. Remove the headlight ECU sub-assembly RH.

      Refer to REMOVAL [09/2019 - 08/2020] , or refer to REMOVAL [08/2020 - ]

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A17-20 (LINL) - C-13 (LINLI) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE HEADLIGHT UNIT ASSEMBLY RH. Refer to  REMOVAL [09/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - ] 

    Result: 

    NG 

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH. Refer to  REMOVAL [09/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - ] 

  7. CHECK HARNESS AND CONNECTOR (HEADLIGHT ECU SUB-ASSEMBLY LH - HEADLIGHT ECU SUB-ASSEMBLY RH) 
    1. Disconnect the A95*1 or A16*2 headlight ECU sub-assembly LH connector.
      1. *1: for TMMT Made
      2. *1: for TMC Made
    2. Disconnect the A17 headlight ECU sub-assembly RH connector.
    3. Measure the resistance according to the value(s) in the chart below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A95-20 (LINL) or A17-20 (LINL) - Body ground*1 Always 10 kΩ or higher
      A16-20 (LINL) or A17-20 (LINL) - Body ground*2 Always 10 kΩ or higher
      1. *1: for TMMT Made
      2. *1: for TMC Made

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CLEAR DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / AFS / Clear DTCs.
    5. Clear the DTCs.

      Body Electrical > AFS > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  9

  9. CHECK FOR DTC 
    1. Disconnect the A17 headlight ECU sub-assembly RH connector.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Wait 10 seconds or more.
    5. Turn the Techstream on.
    6. Enter the following menus: Body Electrical / AFS / Trouble Codes.
    7. Check for DTCs.

      Body Electrical > AFS > Trouble Codes 

      Result

      Result Proceed to
      DTC B2425 is output A
      DTC B2424 and B2425 are output B

    Result: 

    B 

    See step  12

    Result: 

    A 

    See step  10

  10. CLEAR DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / AFS / Clear DTCs.
    5. Clear the DTCs.

      Body Electrical > AFS > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  11

  11. CHECK FOR DTC 
    1. Remove the headlight ECU sub-assembly RH from headlight unit assembly RH.

      Refer to REMOVAL [09/2019 - 08/2020] , or refer to REMOVAL [08/2020 - ]

    2. Reconnect the A17 headlight ECU sub-assembly RH connector.
    3. Connect the Techstream to the DLC3.
    4. Turn the engine switch on (IG).
    5. Wait 10 seconds or more.
    6. Turn the Techstream on.
    7. Enter the following menus: Body Electrical / AFS / Trouble Codes.
    8. Check for DTCs.

      Body Electrical > AFS > Trouble Codes 

      Result

      Result Proceed to
      DTC B2425 is output A
      DTC B2424 and B2425 are output B

    Result: 

    A 

    REPLACE HEADLIGHT UNIT ASSEMBLY RH. Refer to  REMOVAL [09/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - ] 

    Result: 

    B 

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH. Refer to  REMOVAL [09/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - ] 

  12. CLEAR DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / AFS / Clear DTCs.
    5. Clear the DTCs.

      Body Electrical > AFS > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  13

  13. CHECK FOR DTC 
    1. Remove the headlight ECU sub-assembly LH from headlight unit assembly LH.

      Refer to REMOVAL [09/2019 - 08/2020] , or refer to REMOVAL [08/2020 - ]

    2. Reconnect the A16 headlight ECU sub-assembly LH connector.
    3. Connect the Techstream to the DLC3.
    4. Turn the engine switch on (IG).
    5. Wait 10 seconds or more.
    6. Turn the Techstream on.
    7. Enter the following menus: Body Electrical / AFS / Trouble Codes.
    8. Check for DTCs.

      Body Electrical > AFS > Trouble Codes 

      Result

      Result Proceed to
      DTC B2424 is output A
      DTC B2424 and B2425 are output B

    Result: 

    A 

    REPLACE HEADLIGHT UNIT ASSEMBLY LH. Refer to  REMOVAL [09/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - ] 

    Result: 

    B 

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH. Refer to  REMOVAL [09/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - ] 

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