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Home >> Lexus >> 2021 >> RX 350 Base, FWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Exterior Lights >> Lighting System (W/ Automatic Headlight Beam Level Control System) - Diagnostic Codes >> LIGHTING SYSTEM (w/ 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 [08/2019 - ] >> 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 [08/2019 - ]: 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 / Trouble Codes.
    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 [08/2019 - ] 

    Result: 

    C 

    See step  4

    Result: 

    D 

    See step  7

    Result: 

    B 

    See step  3

  3. INSPECT NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH 
    GTY960026Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Replacement Components without harness connected
    (No. 1 Headlight ECU Sub-assembly LH)    		 - -
    1. Remove the No. 1 headlight ECU sub-assembly LH.

      Refer to REMOVAL [08/2019 - ]

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A49-20 (LINL) - C-13 (LINLI) Always Below 1 Ω

      Result

      Result Proceed to
      OK (for TMC Made) A
      OK (for TMMC Made) B
      NG C

    Result: 

    A 

    REPLACE HEADLIGHT UNIT LH. Refer to  DISASSEMBLY [08/2019 - ] 

    Result: 

    B 

    REPLACE HEADLIGHT ASSEMBLY LH. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    C 

    REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH. Refer to  REMOVAL [08/2019 - ] 

  4. CHECK HARNESS AND CONNECTOR (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH - NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH) 
    1. Disconnect the A49 No. 1 headlight ECU sub-assembly LH connector.
    2. Disconnect the A50 No. 1 headlight ECU sub-assembly RH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A49-20 (LINL) - A50-20 (LINL) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH (LINL TERMINAL SIGNAL OUTPUT) 
    GTY960681Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to No. 1 Headlight ECU Sub-assembly RH)
    1. Connect the A49 No. 1 headlight ECU sub-assembly LH connector.
    2. Using a Techstream, check the waveform.

      OK

      Tester Connection Condition Specified Condition
      A50-20 (LINL) - Body ground Engine switch on (IG) Pulse generation

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  6

  6. INSPECT NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH 
    GTY959903Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Replacement Components without harness connected
    (No. 1 Headlight ECU Sub-assembly RH)    		 - -
    1. Remove the No. 1 headlight ECU sub-assembly RH.

      Refer to REMOVAL [08/2019 - ]

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A50-20 (LINL) - C-13 (LINLI) Always Below 1 Ω

      Result

      Result Proceed to
      OK (for TMC Made) A
      OK (for TMMC Made) B
      NG C

    Result: 

    A 

    REPLACE HEADLIGHT UNIT RH. Refer to  DISASSEMBLY [08/2019 - ] 

    Result: 

    B 

    REPLACE HEADLIGHT ASSEMBLY RH. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    C 

    REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH. Refer to  REMOVAL [08/2019 - ] 

  7. CHECK HARNESS AND CONNECTOR (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH - NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH) 
    1. Disconnect the A49 No. 1 headlight ECU sub-assembly LH connector.
    2. Disconnect the A50 No. 1 headlight ECU sub-assembly RH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A49-20 (LINL) or A50-20 (LINL) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CLEAR DTC 
    1. Connect the A49 No. 1 headlight ECU sub-assembly LH connector.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the Techstream on.
    5. Enter the following menus: Body Electrical / AFS / Trouble Codes.
    6. Clear the DTCs.

      Body Electrical > AFS > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  9

  9. 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 

      Result

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

    Result: 

    B 

    See step  13

    Result: 

    A 

    See step  10

  10. CHECK NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH 
    1. Remove the No. 1 headlight ECU sub-assembly RH.

      Refer to REMOVAL [08/2019 - ]

    2. Connect the A50 No. 1 headlight ECU sub-assembly RH connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  11

  11. 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 / Trouble Codes.
    5. Clear the DTCs.

      Body Electrical > AFS > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  12

  12. 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 

      Result

      Result Proceed to
      DTC B2425 is output (for TMC Made) A
      DTC B2425 is output (for TMMC Made) B
      DTC B2424 and B2425 are output C

    Result: 

    A 

    REPLACE HEADLIGHT UNIT RH. Refer to  DISASSEMBLY [08/2019 - ] 

    Result: 

    B 

    REPLACE HEADLIGHT ASSEMBLY RH. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    C 

    REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH. Refer to  REMOVAL [08/2019 - ] 

  13. CHECK NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH 
    1. Remove the No. 1 headlight ECU sub-assembly LH.

      Refer to REMOVAL [08/2019 - ]

    2. Connect the A49 No. 1 headlight ECU sub-assembly LH connector.
    3. Connect the A50 No. 1 headlight ECU sub-assembly RH connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  14. 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 / Trouble Codes.
    5. Clear the DTCs.

      Body Electrical > AFS > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  15

  15. 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 

      Result

      Result Proceed to
      DTC B2424 is output (for TMC Made) A
      DTC B2424 is output (for TMMC Made) B
      DTC B2424 and B2425 are output C

    Result: 

    A 

    REPLACE HEADLIGHT UNIT LH. Refer to  DISASSEMBLY [08/2019 - ] 

    Result: 

    B 

    REPLACE HEADLIGHT ASSEMBLY LH. Refer to  REMOVAL [08/2019 - ] 

    Result: 

    C 

    REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH. Refer to  REMOVAL [08/2019 - ] 

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