LIGHTING SYSTEM, Diagnostic DTC:U0242

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

DESCRIPTION

The headlight ECU sub-assembly LH stores this DTC when the headlight ECU sub-assembly RH detects an internal malfunction or if a communication malfunction occurs between headlight ECU sub-assembly LH and headlight ECU sub-assembly RH for 10 seconds or more.

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

Any of the following conditions is met:


  • Headlight ECU sub-assembly RH internal malfunction

  • Communication malfunction occurs between headlight ECU sub-assembly LH and headlight ECU sub-assembly RH for 10 seconds or more

  • Headlight ECU sub-assembly LH

  • Headlight ECU sub-assembly RH

  • Harness or connector

 -
DTC Detection Conditions:
Vehicle Condition
Pattern 1 Pattern 2
Diagnosis Condition Power switch on (IG) ○ ○
Malfunction Status Headlight ECU sub-assembly RH internal malfunction ○ -
Communication malfunction occurs between headlight ECU sub-assembly LH and headlight ECU sub-assembly RH - ○
Detection Time - 10 seconds or more
Number of Trips 1 trip 1 trip

Tech Tips

DTC will be output when conditions for either of the patterns in the table above are met.

WIRING DIAGRAM

A001PBFE21
*1 LINL
*2 Headlight ECU Sub-assembly LH
*3 Headlight ECU Sub-assembly RH
*4 LIN Communication Line

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


      Body Electrical > HL AutoLeveling > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Turn the power switch on (IG).

    2. Check for DTCs.

      Click here


      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 (HEADLIGHT ECU SUB-ASSEMBLY LH - HEADLIGHT ECU SUB-ASSEMBLY RH)


    1. Disconnect the A16 headlight ECU sub-assembly LH connector.

    2. Disconnect the A17 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
      A16-20 (LINL) - A17-20 (LINL) Always Below 1 Ω
      A16-20 (LINL) or A17-20 (LINL) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH


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

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  5. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > HL AutoLeveling > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK FOR DTC


    1. Turn the power switch on (IG).

    2. Check for DTCs.

      Click here


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

    OK

    END (HEADLIGHT ECU SUB-ASSEMBLY RH WAS DEFECTIVE)

    NG

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH Click here