LIGHTING SYSTEM, Diagnostic DTC:U0242

DTC Code DTC Name
U0242 Lost Communication With Headlamp Control Module "B"

DESCRIPTION

The No. 1 headlight ECU sub-assembly LH stores this DTC when the No. 1 headlight ECU sub-assembly RH detects an internal malfunction or if a communication malfunction occurs between No. 1 headlight ECU sub-assembly LH and No. 1 headlight ECU sub-assembly RH for 10 seconds or more.

DTC No. Detection Item DTC Detection Condition Trouble Area
U0242 Lost Communication With Headlamp Control Module "B"

Either of the following conditions is met:


  • No. 1 headlight ECU sub-assembly RH internal malfunctioning

  • Communication malfunction between No. 1 headlight ECU sub-assembly LH and No. 1 headlight ECU sub-assembly RH is 10 seconds or more

  • No. 1 headlight ECU sub-assembly LH

  • No. 1 headlight ECU sub-assembly RH

  • Harness or connector

WIRING DIAGRAM

A0020XSE23
*1 LINL
*2 No. 1 Headlight ECU Sub-assembly LH
*3 No. 1 Headlight ECU Sub-assembly RH
*4 LIN Communication Line

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 / HL AutoLeveling / Trouble Codes.

    5. Clear the DTCs.


      Body Electrical > HL AutoLeveling > 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 / HL AutoLeveling / Trouble Codes.

    5. Check for DTCs.


      Body Electrical > HL AutoLeveling > Trouble Codes
      OK
      DTC U0242 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

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


    1. Disconnect the W1 No. 1 headlight ECU sub-assembly LH connector.

    2. Disconnect the G1 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
      W1-20 (LINL) - G1-20 (LINL) Always Below 1 Ω
      W1-20 (LINL) or G1-20 (LINL) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. 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

  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 / HL AutoLeveling / Trouble Codes.

    5. Clear the DTCs.


      Body Electrical > HL AutoLeveling > 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 / HL AutoLeveling / Trouble Codes.

    5. Check for DTCs.


      Body Electrical > HL AutoLeveling > Trouble Codes
      OK
      DTC U0242 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