CAN COMMUNICATION SYSTEM Open in One Side of CAN Branch Line

DESCRIPTION

If some ECUs and sensors are not displayed on the "CAN Bus Check" screen of the GTS and some ECUs and sensors repeatedly appear and disappear from the screen when the CAN main bus wires are normal (there is no open, short, short to B+ or short to GND in the main bus wires), there may be an open circuit in either of the CAN branch wires.

Tech Tips

If some ECUs and sensors repeatedly appear and disappear from the "CAN Bus Check" screen, communication between the normal ECUs (sensors) and the GTS may be affected by the incomplete signals that are output from the ECU that has an open circuit in either of its CAN branch wires. In this case, the CAN branch wires for the ECUs and sensors that repeatedly appear and disappear from the screen are normal and the ECU that is not displayed on the screen may be the main cause of the problem (this ECU may have an open circuit in either of its CAN branch wires).

Symptom Trouble Area
2 or more ECUs and/or sensors do not appear on the GTS "CAN Bus Check" screen.

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


  • Power management control ECU

  • ECM

  • Plugin charge control ECU assembly

  • Main body ECU

  • Combination meter assembly

  • Brake booster with master cylinder (Skid control ECU)

  • Steering angle sensor

  • Power steering ECU assembly

  • Yaw rate and acceleration sensor

  • Certification ECU (Smart key ECU assembly)

  • Navigation ECU sub-assembly (Navigation receiver assembly)*1

  • Radio and display receiver assembly*2

*1: for Navigation receiver type

*2: for Radio and display type

INSPECTION PROCEDURE

Tech Tips

Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE


  1. CHECK FOR OPEN IN ONE SIDE OF V1 BUS BRANCH WIRE


    1. Confirm the systems (ECUs and sensors), which use CAN communication, equipped on the vehicle Click here.

    2. Using the GTS, select and perform "CAN Bus Check" Click here.

    3. Observe the screen for approximately 1 minute to check the ECUs and sensors that are not displayed on the screen and also those that repeatedly appear and disappear from the screen.

    4. Check that the ECUs and sensors, which are connected to the ECUs or sensors that are not displayed on the screen.

    5. Check that the ECUs and sensors, which repeatedly appeared and disappeared from the "CAN Bus Check" screen, are constantly displayed.


    NEXT

    GO TO CORRESPONDING COMMUNICATION STOP MODE Click here