CAN COMMUNICATION SYSTEM DIAGNOSIS SYSTEM


  1. BUS CHECK (COMMUNICATION MALFUNCTION ECU)

    Only CAN communication system DTCs for each ECU can be output to the intelligent tester.


    1. A01CHRO

      Select "Bus Check" from the "System Select" screen on the intelligent tester.

    2. A01CH3O

      Select "Communication Malfunction DTC" from the "Bus Check" screen, and then select "Enter".

    3. A01CJ80

      Select the system of the DTC to be checked and select "Details".

    4. A01CGM2

      CAN communication system DTCs are output.

  2. BUS CHECK (COMMUNICATION BUS CHECK)

    Tech Tips

    The ECUs and sensors that are properly connected to the CAN communication system can be displayed using the intelligent tester.


    1. A01CH3O

      Select "Communication Bus Check" from the "Bus Check" screen.

    2. The screen displays the ECUs and sensors that are properly connected to the CAN communication system.

      Tech Tips


      • If any properly connected ECUs or sensors are not displayed, there is a communication stop in the system Click here.

      • The default item displayed in the combo box is "ALL". When checking the ECUs (sensors) connected to each bus, pull down the combo box and select the bus to be checked from the dropdown list. The drop-down list displays "ALL", "V Bus" and the names of the remaining buses.

        Combo Box Display Content
        ALL All ECUs (sensors) connected to the CAN bus
        V Bus ECUs (sensors) connected to the V Bus
        Bus Name ECUs (sensors) connected to the selected bus

      • The connection status (shown below) is indicated by the background color displayed behind the system name.

        ECU (Sensor) on V Bus
        Background Color Connection Status
        White Detected normally
        Yellow Could not be detected in the past, but is currently detected
        Red Detected in the past, but cannot be detected now
        Not displayed Has never been detected
        ECU (Sensor) with No Data Monitor History
        Background Color Connection Status
        White Detected normally
        Yellow Could not be detected in the past, but is currently detected
        Red Detected in the past, but cannot be detected now
        Not displayed Has never been detected
        ECU (Sensor) with Data Monitor History
        Background Color Connection Status
        White Detected normally
        Yellow Could not be detected in the past, but is currently detected
        Red Detected in the past, but cannot be detected now
        Red Has never been detected but has connection history
        Not displayed Has never been detected
    3. A01CJ0T

      "There is no system connected to the communication bus." is displayed if there are no ECUs or sensors connected to the CAN bus.

  3. CHECK INSTALLED SYSTEMS (ECUS AND SENSORS) THAT USE CAN COMMUNICATION


    1. Systems (ECUs and sensors) that use CAN communication vary depending on the optional settings of the vehicle. Check which systems (ECUs and sensors) are installed on the vehicle.

      ECU/Sensor Name Tester Display Installed on
      ECM ECM (Engine) All vehicles
      Electric vehicle control ECU assembly Electric Vehicle Control All vehicles
      Brake actuator assembly (skid control ECU) Skid Control (ABS/VSC/TRAC) All vehicles
      Airbag ECU assembly Airbag All vehicles
      Combination meter assembly Combination Meter All vehicles
      Turbocharger sub-assembly - All vehicles
      EGR valve assembly - All vehicles

  4. DTC TABLE BY ECU

    Tech Tips


    • In the CAN communication system, CAN communication system DTCs stored by the ECU can be output by using the intelligent tester.

    • If CAN communication system DTCs are output, the trouble cannot be determined solely from the DTCs. Perform troubleshooting according to "How to Proceed with Troubleshooting" Click here.


    1. ECM

      Tech Tips

      DTC communication uses the CAN communication system.

      DTC Code Detection Item
      U0129 Lost Communication with Brake System Control Module
      U0155 Lost Communication with Instrument Panel Cluster Control Module (Combination Meter)
      U110A Lost Communication with Vehicle Control
      U1122 Lost Communication with EGR Valve
      U1123 Lost Communication with VN Turbo Module

    2. ELECTRIC VEHICLE CONTROL ECU ASSEMBLY

      Tech Tips

      DTC communication uses the SIL communication system.

      DTC Code Detection Item
      U0105/23 Lost Communication With Fuel Injector Control Module
      U0121/22 Lost Communication With Anti-Lock Brake System (ABS) Control Module
      U0155/22 Lost Communication with Instrument Panel Cluster (IPC) Control Module
      U0418/38 Lost Communication with ABS ECU (Check Sum)

    3. BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU)

      Tech Tips

      DTC communication uses the CAN communication system.

      DTC Code Detection Item
      U0073 Control Module Communication Bus Off
      U0100 Lost Communication With ECM/PCM "A"

    4. COMBINATION METER ASSEMBLY

      Tech Tips

      The combination meter assembly is connected to the CAN communication system but CAN communication DTCs are not stored.

    5. AIRBAG ECU ASSEMBLY

      Tech Tips

      The airbag ECU assembly is connected to the CAN communication system but CAN communication DTCs are not stored.

    6. TURBOCHARGER SUB-ASSEMBLY

      Tech Tips

      The turbocharger sub-assembly is connected to the CAN communication system but CAN communication DTCs are not stored.

    7. EGR VALVE ASSEMBLY

      Tech Tips

      The EGR valve assembly is connected to the CAN communication system but CAN communication DTCs are not stored.

  5. DTC COMBINATION TABLE

    Tech Tips


    • ○: Stored.

    • X: When one side of CAN branch wire is open, storage may occur.

    • -: Not stored.

    Output from Output DTC Detection Item Detected Communication Stop Mode
    V Bus
    ECM Communication Stop Mode Electric Vehicle Control ECU Communication Stop Mode Center Airbag Sensor Communication Stop Mode Brake Actuator (Skid Control ECU) Communication Stop Mode
    ECM U0129 Lost Communication with Brake System Control Module - - - -
    U0155 Lost Communication with Instrument Panel Cluster Control Module (Combination Meter) - - - -
    U110A Lost Communication with Vehicle Control - - - -
    U1122 Lost Communication with EGR Valve - - - -
    U1123 Lost Communication with VN Turbo Module - - - -
    Electric vehicle control ECU assembly U0105/23 Lost Communication With Fuel Injector Control Module - - - -
    U0121/22 Lost Communication With Anti-Lock Brake System (ABS) Control Module X ○ X ○
    U0155/22 Lost Communication with Instrument Panel Cluster (IPC) Control Module - - - -
    U0418/38 Lost Communication with ABS ECU (Check Sum) X ○ X ○
    Brake actuator assembly (skid control ECU) U0073 Control Module Communication Bus Off X X X ○
    U0100 Lost Communication With ECM/PCM "A" ○ X X ○