LIGHTING SYSTEM, 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
U0242 Lost Communication With Headlamp Control Module "B"

Either 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

WIRING DIAGRAM


  1. for Triple Beam Headlight with Adaptive High Beam System

    B002IG3E13

  2. for Triple Beam Headlight without Adaptive High Beam System, for Single Beam Headlight

    B002IZIE07

CAUTION / NOTICE / HINT

Note

After the headlight ECU sub-assembly LH is replaced, vehicle information registration and initialization are necessary.

Click here

PROCEDURE


  1. CONFIRM MODEL


    1. Choose the model to be inspected.

      Result
      Result Proceed to
      for Triple Beam Headlight with Adaptive High Beam System A
      for Triple Beam Headlight without Adaptive High Beam System B
      for Single Beam Headlight

    B

    CHECK FOR DTC Click here

    A

  2. CHECK FOR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > AFS > Clear DTCs

    2. Check for DTCs.

      Click here


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

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  3. CHECK FOR DTC


    1. Turn the power switch on (IG).

    2. Check for DTCs.

      Click here


      Body Electrical > Pre-Collision 2 > Trouble Codes
      OK
      DTC U1002 is not output.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO DTC U1002 Click here

    OK

  4. CHECK CAN BUS WIRES (HEADLIGHT ECU SUB-ASSEMBLY LH)


    1. B002INFC93
      *a

      Front view of wire harness connector

      (to Headlight ECU Sub-assembly LH)

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

    2. Disconnect the 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
      A19-21 (LCL) - A19-22 (LCH) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω

    4. Reconnect the headlight ECU sub-assembly LH connector.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH Click here

    NG

  5. CHECK CAN BUS WIRES (HEADLIGHT ECU SUB-ASSEMBLY RH)


    1. B002INFC95
      *a

      Front view of wire harness connector

      (to Headlight ECU Sub-assembly RH)

      Disconnect the headlight ECU sub-assembly RH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A20-21 (LCL) - A20-22 (LCH) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH Click here

    NG

  6. CHECK HEADLIGHT ECU SUB-ASSEMBLY RH


    1. Replace the headlight light ECU sub-assembly LH with a new.

      Click here

    2. Clear the DTCs.

      Click here


      Body Electrical > AFS > Clear DTCs

    3. Check for DTCs.

      Click here


      Body Electrical > AFS > 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

  7. CHECK FOR DTC


    1. Clear the DTCs.

      Click here

      for Single Beam Headlight:


      Body Electrical > HL AutoLeveling > Clear DTCs

      for Triple Beam Headlight:


      Body Electrical > AFS > Clear DTCs

    2. Check for DTCs.

      Click here

      for Single Beam Headlight:


      Body Electrical > HL AutoLeveling > Trouble Codes

      for Triple Beam Headlight:


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

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  8. CHECK CAN BUS WIRES (HEADLIGHT ECU SUB-ASSEMBLY LH)


    1. B002INFC93
      *a

      Front view of wire harness connector

      (to Headlight ECU Sub-assembly LH)

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

    2. Disconnect the 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
      A19-21 (LCL) - A19-22 (LCH) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      A19-21 (LCL) - GND Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      A19-22 (LCH) - GND Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      A19-21 (LCL) - +B Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      A19-22 (LCH) - +B Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher

    4. Reconnect the headlight ECU sub-assembly LH connector.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH Click here

    NG

  9. CHECK CAN BUS WIRES (HEADLIGHT ECU SUB-ASSEMBLY RH)


    1. B002INFC95
      *a

      Front view of wire harness connector

      (to Headlight ECU Sub-assembly RH)

      Disconnect the headlight ECU sub-assembly RH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A20-21 (LCL) - A20-22 (LCH) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      A20-21 (LCL) - GND Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      A20-22 (LCH) - GND Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      A20-21 (LCL) - +B Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      A20-22 (LCH) - +B Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH Click here

    NG

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR