CAN COMMUNICATION SYSTEM Open in One Side of Bus 2 Branch Line

DESCRIPTION

When the CAN bus main lines are normal (no open, short to ground, short to +B or short between lines) and there is an ECU or sensor on the "Communication Bus Check" screen that is indicated as not communicating or whose connection status on the "Communication Bus Check" screen changes intermittently, an open in one of the wires of a CAN bus branch line is suspected.

Tech Tips

If there is an ECU or sensor whose connection status changes intermittently while checking the "Communication Bus Check" screen, there may be an open circuit in one of the wires of a branch line of an ECU or sensor in the bus. If an open occurs in one of the wires of a CAN branch line, it may interfere with the communication of other ECUs or sensors resulting in an incorrect state being displayed.

Symptom Trouble Area
There is an ECU or sensor that is indicated as not communicating on the "Communication Bus Check" screen or whose connection status on the "Communication Bus Check" screen changes intermittently.

One side of CAN branch line is open, or output signals are incomplete.


  • Power steering ECU assembly

  • Main body ECU (multiplex network body ECU)

  • Steering sensor

  • Airbag sensor assembly

  • Skid control ECU assembly

  • Air conditioning amplifier assembly

  • Certification ECU (smart key ECU assembly)

  • Stereo component equalizer assembly

    (w/ ASC System)

  • Yaw rate sensor

  • Hybrid vehicle control ECU assembly

CAUTION / NOTICE / HINT

Note


  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

    Click here

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

    DTC check procedure: Turn the power switch on (IG) and wait at least 60 seconds. Turn the lane departure alert main switch on and then drive the vehicle at a speed of 36 km/h (22 mph) or more for 300 seconds or more.

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

    Click here

PROCEDURE


  1. CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH LINE


    1. Based on the vehicle equipment and specifications, confirm the systems that use CAN communication.

      Click here

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Turn the GTS on.

    5. Using the GTS, perform "CAN Bus Check".

      Click here


      CAN Bus Check

    6. Observe the screen for approximately 2 minutes to check for ECUs and sensors that are displayed as not communicating.

    7. Perform the inspection as specified in the Problem Symptoms Table for the ECUs or sensors that are not communicating.

      Result
      Proceed to
      NEXT

    NEXT

    GO TO CORRESPONDING COMMUNICATION STOP MODE Click here