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 malfunctions in the automatic high beam system.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B124B

Automatic High Beam System

Malfunction in automatic high beam system

  • Brake control system

  • Airbag sensor assembly (yaw rate and acceleration sensor)

  • CAN communication system

  • Inner rear view mirror assembly (automatic high beam sensor)

  • AFS ECU (headlight swivel ECU assembly)

WIRING DIAGRAM

E261658E02

CAUTION / NOTICE / HINT

Note:

  • First perform the communication function inspections in Diagnosis System to confirm that there are no CAN communication malfunctions before performing the following inspection.

    Click hereClick hereClick here

  • Inspect the inner rear view mirror assembly before performing the following procedure.

    Click here

  • If the AFS ECU (headlight swivel ECU assembly) has been replaced, it is necessary to synchronize the vehicle information and initialize the AFS ECU (headlight swivel ECU assembly).

    Click here

PROCEDURE

  1. CHECK FOR DTC

    1. Clear the DTCs.

      Click here

      Body Electrical > Main Body > Clear DTCs

    2. Check for DTCs.

      Click here

      Body Electrical > Main Body > Trouble Codes

      OK

      DTC B124B is not output.

    Result

    Proceed to

    OK

    NG
    OK

    USE SIMULATION METHOD TO CHECK

    Click hereClick hereClick here

    NG

  2. CHECK FOR DTC

    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

    Result

    Proceed to

    Only DTC B124B is output

    A

    DTC B2414 or B2415 is output

    B

    CAN communication system DTCs are output

    C
    B

    GO TO DIAGNOSTIC TROUBLE CODE CHART (AFS (ADAPTIVE FRONT-LIGHTING SYSTEM))

    Click hereClick here

    C

    GO TO CAN COMMUNICATION SYSTEM

    Click here

    A

  3. CHECK INNER REAR VIEW MIRROR ASSEMBLY

    1. Replace the inner rear view mirror assembly with a new or known good one.

      Click here

    2. Check for DTCs.

      Click here

      Body Electrical > Main Body > Trouble Codes

      OK

      DTC B124B is not output.

    Result

    Proceed to

    OK

    NG
    OK

    END (INNER REAR VIEW MIRROR ASSEMBLY (AUTOMATIC HIGH BEAM SENSOR) WAS DEFECTIVE)

    NG

    REPLACE AFS ECU (HEADLIGHT SWIVEL ECU ASSEMBLY)

    Click here