AUTOMATIC HIGH BEAM SYSTEM, Diagnostic DTC:B124B

DTC Code DTC Name
B124B Automatic High Beam System

DESCRIPTION

This DTC is stored when the main body ECU (multiplex network body ECU) detects malfunction in the automatic high beam system.

When DTCs for the following systems are stored, this DTC is stored simultaneously.


DTC No. Detection Item DTC Detection Condition Trouble Area
B124B Automatic High Beam System Malfunction in automatic high beam system

  • Lane departure alert system

  • CAN communication system

  • Main body ECU (multiplex network body ECU)

WIRING DIAGRAM


  1. A01QSJJE01
    *1 Main Body ECU (Multiplex Network Body ECU)
    *2 Lane Departure Warning Camera
    *3 CAN Communication Line

CAUTION / NOTICE / HINT

Note


  • First perform the communication function inspections in How to Proceed with Troubleshooting to confirm that there are no CAN communication malfunctions before troubleshooting this DTC.

  • When the lane departure warning camera is replaced with a new one, adjustment of the lane departure warning camera beam axis must be performed.

    Click here

  • When replacing the main body ECU (multiplex network body ECU), make sure to replace it with a new one.

PROCEDURE


  1. CHECK FOR DTC (AUTOMATIC HIGH BEAM SYSTEM)


    1. Clear the DTCs.

      Click here


      Body Electrical > Main Body > Clear DTCs

    2. Check for DTCs.

      Click here


      Body Electrical > Main Body > Trouble Codes
      Result
      Proceed to
      DTC B124B is not output
      DTC B124B is output

    DTC B124B is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B124B is output

  2. CHECK FOR DTC (ALL)


    1. Connect the GTS to DLC3.

    2. Turn the ignition switch to ON.

    3. Enter the following menus: System Select / Health Check.

    4. Check for DTCs.

      Result
      Proceed to
      Lane departure alert system DTCs are not output
      Lane departure alert system DTCs are output
      CAN communication system DTCs are output

    Lane departure alert system DTCs are output

    GO TO LANE DEPARTURE ALERT SYSTEM Click here

    CAN communication system DTCs are output

    GO TO CAN COMMUNICATION SYSTEM Click here

    Lane departure alert system DTCs are not output

  3. CHECK LANE DEPARTURE WARNING CAMERA


    1. Temporarily replace the lane departure warning camera with a new or normally functioning one.

      Click here

    2. Check for DTCs.

      Click here


      Body Electrical > Main Body > Trouble Codes
      Result
      Proceed to
      DTC B124B is not output
      DTC B124B is output

    DTC B124B is not output

    END (LANE DEPARTURE WARNING CAMERA WAS DEFECTIVE)

    DTC B124B is output

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here