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Home >> Lexus >> 2024 >> RC 350 Base, RWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 3 (Lighting System (Triple Beam Headlight) - Diagnostic Codes & Circuit Tests) >> LIGHTING SYSTEM (for Triple Beam Headlight) >> DTC B242C: Right Headlight ECU Malfunction; DTC B242D: Left Headlight ECU Malfunction [09/2014 - 10/2018] >> Procedure

DTC B242C: Right Headlight ECU Malfunction; DTC B242D: Left Headlight ECU Malfunction [09/2014 - 10/2018]: Procedure

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  1. CLEAR DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2014 - 10/2018]

      Body Electrical > HL AutoLeveling > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. CHECK FOR DTC 
    1. Turn the engine switch on (IG).
    2. Clear the DTCs.
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [09/2014 - 10/2018]

      Body Electrical > HL AutoLeveling > Trouble Codes 

      OK

      DTC B242C and B242D are not output.

      Result

      Result Proceed to
      OK A
      NG (DTC B242C is output) B
      NG (DTC B242D is output) C

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2014 - 10/2015]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - 11/2017]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 10/2018] 

    Result: 

    B 

    REPLACE HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY RH. Refer to  REMOVAL [09/2014 - 10/2018] 

    Result: 

    C 

    REPLACE HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH. Refer to  REMOVAL [09/2014 - 10/2018]