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.
By pairing the CANH and CANL bus lines, the CAN performs communication based on differential voltages.
Many ECUs (sensors) installed on the vehicle operate by sharing information and communicating with each other.
The CAN has 2 resistors of 120 Ω which are necessary to communicate using the main wire.
DEFINITION OF TERMS
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.
The branch wire is a wire harness which diverges from the main wire to an ECU or sensor.
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 capacitor. 2 termination circuits are necessary on a bus.
CAN junction connector
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.
The V bus, powertrain bus and local bus each have termination circuits with a resistance of 120 Ω x 2. High speed communication at 500 kbps and 250 kbps is possible.
ECUS OR SENSORS WHICH COMMUNICATE VIA CAN COMMUNICATION SYSTEM
CAN V Bus
Center airbag sensor assembly
Skid control ECU (brake actuator assembly)
Engine stop and start ECU*1
Certification ECU (smart key ECU assembly)*2
Steering angle sensor (spiral cable sub-assembly)*3
Radio and display receiver assembly*4
Air conditioning amplifier assembly*5
Main body ECU (multiplex network body ECU)
Power steering ECU assembly
Combination meter assembly
Network gateway ECU*7
Option connector (bus buffer ECU)*7
*1: w/ Stop and Start System
*2: w/ Entry and Start System
*3: w/ VSC
*4: w/ Display
*5: w/ Air Conditioning System or PTC Heater
*6: except GRMN
*7: for GRMN
CAN Local Bus*1
Network gateway ECU
*1: for GRMN
DIAGNOSTIC CODES FOR CAN COMMUNICATION SYSTEM
See Diagnosis System Click here.
NOTES REGARDING TROUBLESHOOTING
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).
DTCs regarding the CAN communication system can be checked using the GTS.
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.
HOW TO DISTINGUISH CAN JUNCTION CONNECTOR CONNECTORS
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.
Refer to "Terminals of ECU" Click here for bus line color or the connecting side of the connector.