LIGHTING SYSTEM, Diagnostic DTC:B2439, B243A

DTC Code DTC Name
B2439 Headlamp LH Circuit
B243A Headlamp RH Circuit

DESCRIPTION

A DTC is stored when the headlight ECU sub-assembly receives a light source malfunction signal from its respective headlight unit. The headlight ECU sub-assembly LH stores DTC B2439 and B243A.

DTC Code DTC Detection Condition Trouble Area
B2439 Headlight ECU sub-assembly LH light source malfunction

  • Headlight unit assembly LH

  • Headlight unit LH

  • Headlight ECU sub-assembly LH
B243A Headlight ECU sub-assembly RH light source malfunction

  • Headlight unit assembly RH

  • Headlight unit RH

  • Headlight ECU sub-assembly RH

WIRING DIAGRAM


  1. for Single Beam Headlight without AFS (Adaptive Front-lighting System)

    B002BIXE19

  2. for Single Beam Headlight with AFS (Adaptive Front-lighting System)

    B002BIXE20

  3. for Triple Beam Headlight

    B002BVZE13
    *a Lo Beam
    *b Headlight Unit Assembly
    *c Headlight Unit
    *d Headlight ECU Sub-assembly

CAUTION / NOTICE / HINT

Note

If the headlight ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information and initialize the headlight ECU sub-assembly LH Click here.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Turn the power switch on (IG).

    2. Operate the light control switch to turn on the low beam headlights and then turn on the high beam headlights.

    3. Check for DTCs Click here.

      OK
      DTC B2439 and B243A are not output.
      Result
      Result Proceed to
      OK A
      NG (DTC B2439 is output) B
      NG (DTC B243A is output) C

    A

    USE SIMULATION METHOD TO CHECK Click here

    C

    INSPECT HEADLIGHT UNIT ASSEMBLY RH Click here

    B

  3. INSPECT HEADLIGHT UNIT LH


    1. Remove the headlight assembly LH.


    2. Remove the headlight unit LH.


    3. for Single Beam Headlight:

      B002BQNE02
      Text in Illustration
      *A without AFS (Adaptive Front-lighting System) *B with AFS (Adaptive Front-lighting System)
      *a

      Component without harness connected

      (to Headlight Unit Assembly LH)

      		 *b

      Component without harness connected

      (to Headlight ECU Sub-assembly LH)

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

        Standard Resistance
        without AFS (Adaptive Front-lighting System)
        Tester Connection Condition Specified Condition
        B-4 - D-5 Always Below 1 Ω
        B-5 - D-6 Always Below 1 Ω
        with AFS (Adaptive Front-lighting System)
        Tester Connection Condition Specified Condition
        B-4 - D-3 Always Below 1 Ω
        B-3 - D-5 Always Below 1 Ω
    4. B002BUUE02
      Text in Illustration
      *a

      Component without harness connected

      (to Headlight Unit Assembly LH)
      *b

      Component without harness connected

      (to Headlight ECU Sub-assembly LH)

      for Triple Beam Headlight:


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

        Standard Resistance
        Tester Connection Condition Specified Condition
        B-4 - G-2 Always Below 1 Ω
        B-3 - G-1 Always Below 1 Ω
      Result
      Result Proceed to
      OK A
      NG (for Single Beam Headlight) B
      NG (for Triple Beam Headlight) C

    B

    REPLACE HEADLIGHT UNIT LH Click here

    C

    REPLACE HEADLIGHT UNIT LH Click here

    A

  4. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  5. CHECK FOR DTC


    1. Turn the power switch on (IG).

    2. Operate the light control switch to turn on the low beam headlights and then turn on the high beam headlights.

    3. Check for DTCs Click here.

      OK
      DTC B2439 is not output.

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  6. REPLACE HEADLIGHT UNIT ASSEMBLY LH


    1. Replace the headlight unit assembly LH with a new or known good one.



    NEXT

  7. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  8. CHECK FOR DTC


    1. Turn the power switch on (IG).

    2. Operate the light control switch to turn on the low beam headlights and then turn on the high beam headlights.

    3. Check for DTCs Click here.

      OK
      DTC B2439 is not output.

    OK

    END (HEADLIGHT UNIT ASSEMBLY LH WAS DEFECTIVE)

    NG

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH Click here

  9. INSPECT HEADLIGHT UNIT ASSEMBLY RH


    1. Remove the headlight assembly RH.


    2. Remove the headlight unit RH.


    3. for Single Beam Headlight:

      B002BQNE02
      Text in Illustration
      *A without AFS (Adaptive Front-lighting System) *B with AFS (Adaptive Front-lighting System)
      *a

      Component without harness connected

      (to Headlight Unit Assembly RH)

      		 *b

      Component without harness connected

      (to Headlight ECU Sub-assembly RH)

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

        Standard Resistance
        without AFS (Adaptive Front-lighting System)
        Tester Connection Condition Specified Condition
        B-4 - D-5 Always Below 1 Ω
        B-5 - D-6 Always Below 1 Ω
        with AFS (Adaptive Front-lighting System)
        Tester Connection Condition Specified Condition
        B-4 - D-3 Always Below 1 Ω
        B-3 - D-5 Always Below 1 Ω
    4. B002BUUE02
      Text in Illustration
      *a

      Component without harness connected

      (to Headlight Unit Assembly RH)
      *b

      Component without harness connected

      (to Headlight ECU Sub-assembly RH)

      for Triple Beam Headlight:


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

        Standard Resistance
        Tester Connection Condition Specified Condition
        B-4 - G-2 Always Below 1 Ω
        B-3 - G-1 Always Below 1 Ω
      Result
      Result Proceed to
      OK A
      NG (for Single Beam Headlight) B
      NG (for Triple Beam Headlight) C

    B

    REPLACE HEADLIGHT UNIT RH Click here

    C

    REPLACE HEADLIGHT UNIT RH Click here

    A

  10. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  11. CHECK FOR DTC


    1. Turn the power switch on (IG).

    2. Operate the light control switch to turn on the low beam headlights and then turn on the high beam headlights.

    3. Check for DTCs Click here.

      OK
      DTC B243A is not output.

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  12. REPLACE HEADLIGHT ASSEMBLY UNIT RH


    1. Replace the headlight unit assembly RH with a new or known good one.



    NEXT

  13. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  14. CHECK FOR DTC


    1. Turn the power switch on (IG).

    2. Operate the light control switch to turn on the low beam headlights and then turn on the high beam headlights.

    3. Check for DTCs Click here.

      OK
      DTC B243A is not output.

    OK

    END (HEADLIGHT ASSEMBLY UNIT RH WAS DEFECTIVE)

    NG

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH Click here