AUTOMATIC HIGH BEAM SYSTEM, Diagnostic DTC:B124B

DTC Code DTC Name
B124B Automatic High Beam System

DESCRIPTION

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


DTC No. DTC Detection Condition Trouble Area
B124B

Malfunction in automatic high beam system

(Detected for 2 seconds or more)

  • Lane departure alert system

  • CAN communication system

  • Lane departure warning camera

  • Driving support ECU assembly*1

  • Main body ECU (multiplex network body ECU)

WIRING DIAGRAM


  1. w/ Dynamic Radar Cruise Control System

    A0005FTE01

  2. w/o Dynamic Radar Cruise Control System

    A0007Z5E01
    *1 Lane Departure Warning Camera
    *2 Power Management Control ECU
    *3 Main Body ECU (Multiplex Network Body ECU)
    *4 CAN Communication Line

CAUTION / NOTICE / HINT

Note

If the main body ECU (multiplex network body ECU) is replaced, refer to Service Bulletin.

PROCEDURE


  1. CHECK FOR DTC (AUTOMATIC HIGH BEAM SYSTEM)


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B124B is not output.
      Result
      Result Proceed to
      DTC B124B is not output A

      DTC B124B is output

      (w/ Dynamic Radar Cruise Control System)

      		 B

      DTC B124B is output

      (w/o Dynamic Radar Cruise Control System)

      		 C

    A

    USE SIMULATION METHOD TO CHECK Click here

    C

    CHECK FOR DTC (LANE DEPARTURE ALERT SYSTEM) Click here

    B

  2. CHECK FOR DTC (LANE DEPARTURE ALERT SYSTEM)


    1. Check for DTCs Click here.

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

    B

    GO TO LANE DEPARTURE ALERT SYSTEM Click here

    C

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  3. REPLACE LANE DEPARTURE WARNING CAMERA


    1. Replace the lane departure warning camera with a new or known good one Click here.

    2. Check for DTCs Click here.

      OK
      DTC B124B is not output.

    OK

    END (LANE DEPARTURE WARNING CAMERA WAS DEFECTIVE)

    NG

  4. REPLACE DRIVING SUPPORT ECU ASSEMBLY


    1. Replace the driving support ECU assembly with a new or known good one Click here.

    2. Check for DTCs Click here.

      OK
      DTC B124B is not output.

    OK

    END (DRIVING SUPPORT ECU ASSEMBLY WAS DEFECTIVE)

    NG

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

  5. CHECK FOR DTC (LANE DEPARTURE ALERT SYSTEM)


    1. Check for DTCs Click here.

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

    B

    GO TO LANE DEPARTURE ALERT SYSTEM Click here

    C

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  6. REPLACE LANE DEPARTURE WARNING CAMERA


    1. Replace the lane departure warning camera with a new or known good one Click here.

    2. Check for DTCs Click here.

      OK
      DTC B124B is not output.

    OK

    END (LANE DEPARTURE WARNING CAMERA WAS DEFECTIVE)

    NG

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