LIGHTING SYSTEM, Diagnostic DTC:B124D, B2432

DTC Code DTC Name
B124D Lost Communication with AFS LIN
B2432 Lost Communication with Automatic High Beam Sensor

DESCRIPTION


DTC Code DTC Detection Condition Trouble Area
B124D Malfunction in LIN communication system

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

  • Harness or connector

  • Headlight swivel ECU assembly
B2432 Malfunction in LIN communication system

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

  • Harness or connector

  • Headlight swivel ECU assembly

WIRING DIAGRAM

A01FDJLE02

INSPECTION PROCEDURE

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.

  • After replacing the headlight swivel ECU, perform initialization and registration of vehicle information Click here.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs Click here.

      OK
      DTC B124D or B2432 output does not occur.

    NG

    CHECK HARNESS AND CONNECTOR (HEADLIGHT SWIVEL ECU - INNER REAR VIEW MIRROR) Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  3. CHECK HARNESS AND CONNECTOR (HEADLIGHT SWIVEL ECU - INNER REAR VIEW MIRROR)


    1. Disconnect the A7 headlight swivel ECU connector.

    2. Disconnect the Y8 inner rear view mirror connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A7-11 (RH+) - Y8-10 (LIN) Always Below 1 Ω
      A7-11 (RH+) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HEADLIGHT SWIVEL ECU ASSEMBLY


    1. A01FIGFE01

      Disconnect the inner rear view mirror connector.

    2. A01FE03E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Inner Rear View Mirror Assembly [Automatic High Beam Sensor])

      Using an oscilloscope, measure the waveform at the connector of the vehicle wire harness.

      Measurement Condition
      Item Content
      Terminal No. (Symbol) Y8-10 (LIN) - Body ground
      Tool setting 2 V/DIV., 10 ms./DIV.
      Condition Automatic high beam system operates
      OK
      Waveform is as shown in the illustration.
      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    B

    REPLACE HEADLIGHT SWIVEL ECU ASSEMBLY Click here

    C

    REPLACE HEADLIGHT SWIVEL ECU ASSEMBLY Click here

    A

    REPLACE INNER REAR VIEW MIRROR ASSEMBLY (AUTOMATIC HIGH BEAM SENSOR) Click here