LIGHTING SYSTEM, Diagnostic DTC:U0242

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

DESCRIPTION

This DTC is output when a headlight light control ECU sub-assembly RH (sub) internal malfunctioning or the communication malfunction between headlight light control ECU sub-assembly LH (main) and headlight light control ECU sub-assembly RH (sub) is 10 seconds or more.

The headlight light control ECU sub-assembly LH (main) outputs DTC U0242.

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

  • Either conditions:


    • Headlight light control ECU sub-assembly RH (sub) internal malfunctioning

    • The communication malfunction between headlight light control ECU sub-assembly LH (main) and headlight light control ECU sub-assembly RH (sub) is 10 seconds or more.

  • Headlight light control ECU sub-assembly LH (main)

  • Headlight light control ECU sub-assembly RH (sub)

  • Harness or connector

WIRING DIAGRAM

B006NXCE14
*1 LINL
*2 Headlight Light Control ECU Sub-assembly LH (Main)
*3 Headlight Light Control ECU Sub-assembly RH (Sub)
*4 LIN Communication Line

CAUTION / NOTICE / HINT

Note

After the headlight light control ECU sub-assembly LH (main) is replaced, vehicle information registration and initialization are necessary.

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 engine switch on (IG).

    2. Turn on the headlights using the headlight dimmer switch.

    3. Check for DTCs.

      Click here


      Body Electrical > HL AutoLeveling > Trouble Codes
      Result
      Proceed to
      DTC U0242 output does not occur
      DTC U0242 output occurs

    DTC U0242 output does not occur

    USE SIMULATION METHOD TO CHECK Click here

    DTC U0242 output occurs

  3. CHECK HARNESS AND CONNECTOR (HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH [MAIN] - HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY RH [SUB])


    1. Disconnect the A28 headlight light control ECU sub-assembly LH (main) connector.

    2. Disconnect the A29 headlight light control ECU sub-assembly RH (sub) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A28-20 (LINL) - A29-20 (LINL) Always Below 1 Ω
      A28-20 (LINL) or A29-20 (LINL) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY RH (SUB)


    1. Replace the headlight light control ECU sub-assembly RH (sub) with a new or normally functioning 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 engine switch on (IG).

    2. Turn on the headlights using the headlight dimmer switch.

    3. Check for DTCs.

      Click here


      Body Electrical > HL AutoLeveling > Trouble Codes
      Result
      Proceed to
      DTC U0242 output does not occur
      DTC U0242 output occurs

    DTC U0242 output does not occur

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

    DTC U0242 output occurs

    REPLACE HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH (MAIN) Click here