LIGHTING SYSTEM(for LED Headlight), Diagnostic DTC:U0242

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

DESCRIPTION

DTC No. Detection Item DTC Detection Condition Trouble Area DTC Output from Note
U0242 Lost Communication With Headlamp Control Module "B" The No. 1 headlight ECU sub-assembly LH does not receive data from the No. 1 headlight ECU sub-assembly RH for approximately 10 seconds or more.

  • Harness or connector

  • No. 1 headlight ECU sub-assembly LH

  • No. 1 headlight ECU sub-assembly RH

 No. 1 headlight ECU sub-assembly LH -

WIRING DIAGRAM

B001DMYE01

CAUTION / NOTICE / HINT

Note


  • Inspect the fuse for circuits related to this system before performing the follow ingprocedure.

  • 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. CHECK DTC


    1. Clear the DTCs.

      Click here

    2. Turn the ignition switch to ON and wait for at least 10 seconds or more.

    3. Check for DTCs.

      Click here

      OK
      DTC U0242 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK

    NG

  2. CHECK HARNESS AND CONNECTOR (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH - BATTERY AND BODY GROUND)


    1. B001EKKC97
      *a

      Front view of wire harness connector

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

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

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A103-4 (IG) - Body ground Ignition switch ON 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A103-12 (GND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK FOR CAN BUS WIRE (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH CAN MAIN WIRE)


    1. B001EKKC98
      *a

      Front view of wire harness connector

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

      Disconnect the cable from the negative (-) battery terminal.

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A102-22 (LCH) - A102-21 (LCL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      A102-22 (LCH) - +B Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      A102-21 (LCL) - +B Cable disconnected from negative (-) battery terminal 200 Ω or higher
      A102-22 (LCH) - GND Cable disconnected from negative (-) battery terminal 200 Ω or higher
      A102-21 (LCL) - GND Cable disconnected from negative (-) battery terminal 200 Ω or higher
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

  4. CHECK FOR CAN BUS WIRE (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH CAN MAIN WIRE)


    1. B001EKKC99
      *a

      Front view of wire harness connector

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

      Disconnect the cable from the negative (-) battery terminal.

    2. Disconnect the 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
      A103-22 (LCH) - A103-21 (LCL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      A103-22 (LCH) - +B Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      A103-21 (LCL) - +B Cable disconnected from negative (-) battery terminal 200 Ω or higher
      A103-22 (LCH) - GND Cable disconnected from negative (-) battery terminal 200 Ω or higher
      A103-21 (LCL) - GND Cable disconnected from negative (-) battery terminal 200 Ω or higher
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR