CAN COMMUNICATION SYSTEM (for LHD) SYSTEM DESCRIPTION


  1. BRIEF DESCRIPTION


    1. The CAN (Controller Area Network) is a serial data communication system for real time application. It is a vehicle multiplex communication system which has a high communication speed (500 kbps, 250 kbps) and the ability to detect malfunctions.

    2. By pairing the CANH and CANL bus lines, the CAN performs communication based on differential voltages.

    3. Many ECUs (sensors) installed on the vehicle operate by sharing information and communicating with each other.

    4. The CAN has 2 resistors of 120 Ω which are necessary to communicate with the main wire.

  2. DEFINITION OF TERMS


    1. Main wire


      1. The main wire is a wire harness between the 2 termination circuits on the bus (communication line). This is the main bus in the CAN communication system.

    2. Branch wire


      1. The branch wire is a wire harness which diverges from the main wire to an ECU or sensor.

    3. Termination circuits


      1. The termination circuit is a circuit which converts the communication current of the CAN communication into the bus voltage. It consists of a resistor and condenser. 2 termination circuits are necessary on a bus.

    4. CAN junction connector


      1. The CAN junction connector is designed so that it can be used with CAN communication which has a termination circuit and CAN communication which does not have a termination circuit.

  3. CIRCUIT DESCRIPTION


    1. The V bus, movement control bus and MS bus each have termination circuits with resistance of 120 Ω x 2. High speed communication at 500 kbps and 250 kbps is possible.

  4. ECU OR SENSOR WHICH COMMUNICATE VIA CAN COMMUNICATION SYSTEM


    1. Master cylinder solenoid (skid control ECU)

    2. Air conditioning amplifier assembly

    3. ECM

    4. Main body ECU (cowl side junction block LH)

    5. Combination meter assembly

    6. Center airbag sensor assembly

    7. Multi-media module receiver assembly

    8. Steering angle sensor

    9. Yaw rate sensor assembly

    10. Seat belt control ECU*1

    11. Clearance warning ECU assembly*2

    12. Parking assist ECU*3

    13. Outer mirror control ECU assembly

    14. Multiplex tilt and telescopic ECU

    15. Certification ECU (smart key ECU assembly)

    16. Position control ECU and switch

    17. Network gateway ECU

    18. 4WD control ECU

    19. No. 2 main body ECU

    20. Power back door unit assembly (power back door ECU)*4

    21. Distance control ECU assembly*5

    22. Tire pressure warning ECU

    23. Steering control ECU

    24. Suspension control ECU

    25. Headlight swivel ECU assembly (AFS ECU )

    26. Windshield wiper ECU


      • *1: w/ Pre-crash Safety System

      • *2: w/o Side Monitor System

      • *3: w/ Side Monitor System

      • *4: w/ Power Back Door System

      • *5: w/ Dynamic Radar Cruise Control System

  5. DIAGNOSTIC CODES FOR CAN COMMUNICATION SYSTEM


    1. DTCs for the CAN communication system are as follows: U0073, U0100, U0101, U0104, U0114/38, U0122, U0123, U0124, U0125, U0126, U0127, U0129, U0130, U0132, U0140, U0141, U0151, U0155, U0199, U0208, U0230, U0235, U0327, U1002 (CAN MS BUS), U1002 (CAN No. 2 BUS), U1100, U1101, U1102, U110B, U1110, U1111, U1115, B2427, B2621, B2624, C2179 and C1AEF.

  6. NOTES REGARDING TROUBLESHOOTING


    1. Trouble in the CAN bus (communication line) can be checked through the DLC3 (except when there is a wire break in the branch wire of the DLC3).

    2. DTCs regarding the CAN communication system can be checked using the intelligent tester.

    3. The CAN communication system cannot detect trouble in the branch line of the DLC3 even though the DLC3 is also connected to the CAN communication system.

  7. HOW TO DISTINGUISH CAN JUNCTION CONNECTOR CONNECTOR


    1. In the CAN communication system, the shape of all connectors connected to the CAN junction connector is the same.

      The connectors connected to the CAN junction connector can be distinguished by the colors of the bus line and the connecting side of the connector.

      Tech Tips

      See "Terminals of ECU" Click here for bus line color or the type of connecting surface.