ADAPTIVE HIGH BEAM SYSTEM, Diagnostic DTC:B2440, B2441

DTC Code DTC Name
B2440 Lost Communication with AHS EDU LH Module
B2441 Lost Communication with AHS EDU RH Module

DESCRIPTION

The No. 1 headlight ECU sub-assembly communicates with the headlight light control ECU sub-assembly via LIN communication. When a communication error between the No. 1 headlight ECU sub-assembly and headlight light control ECU sub-assembly is detected, the No. 1 headlight ECU sub-assembly LH stores DTC B2440 and B2441.

DTC No. Detection Item DTC Detection Condition Trouble Area
B2440 Lost Communication with AHS EDU LH Module Headlight light control ECU sub-assembly LH communication error

  • Headlight unit assembly LH

  • Headlight light control ECU sub-assembly LH

  • No. 1 headlight ECU sub-assembly LH
B2441 Lost Communication with AHS EDU RH Module Headlight light control ECU sub-assembly RH communication error

  • Headlight unit assembly RH

  • Headlight light control ECU sub-assembly RH

  • No. 1 headlight ECU sub-assembly LH

  • No. 1 headlight ECU sub-assembly RH

  • Harness or connector

WIRING DIAGRAM

A003K53E04

CAUTION / NOTICE / HINT

Note

If the No. 1 headlight ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information and initialize the No. 1 headlight ECU sub-assembly LH.

Click here

PROCEDURE


  1. CLEAR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / AHS / Trouble Codes.

    5. Clear the DTCs.


      Body Electrical > AHS > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / AHS / Trouble Codes.

    5. Check for DTCs.


      Body Electrical > AHS > Trouble Codes
      OK
      DTC B2440 and B2441 are not output.
      Result
      Result Proceed to
      OK A
      NG (DTC B2440 is output) B
      NG (DTC B2441 is output) C

    A

    USE SIMULATION METHOD TO CHECK Click here

    C

    CHECK HARNESS AND CONNECTOR (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH - NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH) Click here

    B

  3. INSPECT HEADLIGHT UNIT ASSEMBLY LH

    A003OX7C02
    *a

    Component without harness connected

    (to No. 1 Headlight ECU Sub-assembly LH)

    		 *b

    Component without harness connected

    (to Headlight Light Control ECU Sub-assembly LH)

    1. Remove the headlight assembly LH.

      Click here

    2. Remove the headlight unit LH.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B-10 (HI+) - K-10 (LB) Always Below 1 Ω
      B-1 (HI-) - K-1 (LG) Always Below 1 Ω
      C-13 (LINI) - K-9 (LIN) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE HEADLIGHT UNIT ASSEMBLY LH Click here

    OK

  4. REPLACE HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH


    1. Replace the headlight light control ECU sub-assembly LH with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  5. CLEAR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / AHS / Trouble Codes.

    5. Clear the DTCs.


      Body Electrical > AHS > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK FOR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / AHS / Trouble Codes.

    5. Check for DTCs.


      Body Electrical > AHS > Trouble Codes
      OK
      DTC B2440 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH WAS DEFECTIVE)

    NG

    REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH Click here

  7. CHECK HARNESS AND CONNECTOR (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH - NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH)


    1. Disconnect the A15 No. 1 headlight ECU sub-assembly LH connector.

    2. Disconnect the A16 No. 1 headlight ECU sub-assembly RH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A15-20 (LINL) - A16-20 (LINL) Always Below 1 Ω
      A15-20 (LINL) or A16-20 (LINL) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. INSPECT HEADLIGHT UNIT ASSEMBLY RH

    A003OX7C02
    *a

    Component without harness connected

    (to No. 1 Headlight ECU Sub-assembly RH)

    		 *b

    Component without harness connected

    (to Headlight Light Control ECU Sub-assembly RH)

    1. Remove the headlight assembly RH.

      Click here

    2. Remove the headlight unit RH.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B-10 (HI+) - K-10 (LB) Always Below 1 Ω
      B-1 (HI-) - K-1 (LG) Always Below 1 Ω
      C-13 (LINI) - K-9 (LIN) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE HEADLIGHT UNIT ASSEMBLY RH Click here

    OK

  9. REPLACE HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY RH


    1. Replace the headlight light control ECU sub-assembly RH with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  10. CLEAR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / AHS / Trouble Codes.

    5. Clear the DTCs.


      Body Electrical > AHS > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  11. CHECK FOR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / AHS / Trouble Codes.

    5. Check for DTCs.


      Body Electrical > AHS > Trouble Codes
      OK
      DTC B2441 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY RH WAS DEFECTIVE)

    NG

  12. REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH


    1. Replace the No. 1 headlight ECU sub-assembly RH with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  13. CLEAR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / AHS / Trouble Codes.

    5. Clear the DTCs.


      Body Electrical > AHS > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  14. CHECK FOR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / AHS / Trouble Codes.

    5. Check for DTCs.


      Body Electrical > AHS > Trouble Codes
      OK
      DTC B2441 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH WAS DEFECTIVE)

    NG

    REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH Click here