Description
DESCRIPTION1. BRIEF DESCRIPTION
a. The CAN (Controller Area Network) is a serial data communication system for real time application. It is a multiplex communication system equipped for a vehicle and has a high communication speed (500 kbps) and the function to detect malfunctions.
b. By pairing the CANH and CANL bus lines, the CAN performs communication based on differential voltage.
c. The RX330 uses CAN communication system for the communication between the ECU and sensors in the ABS with EBD & BA & TRAC & VSC system.
d. The CAN has two resistors of 120 Ohms which are necessary to communicate with the main bus line.
2. DEFINITION OF TERMS
a. Main bus line
1. Main bus line is the wire harness between the two terminus circuits on the bus (communication line). This is the main bus in the CAN communication system.
b. Sub bus line
1. Sub bus line is the wire harness which diverges from the main bus line to the ECU or sensor.
c. Terminus circuit
1. Terminus circuit is a circuit which is placed to convert communication current of the CAN communication into bus voltage and it consists of a resistor and condenser. Two terminus circuits are necessary on a bus.
d. CAN J/C
1. CAN J/C is a junction which is designed for the CAN communication system, and it has a terminus circuit built in.
3. ECU OR SENSORS WHICH COMMUNICATE THROUGH CAN COMMUNICATION SYSTEM
a. Skid Control ECU with Actuator (VSC ECU)
b. Yaw Rate Sensor (with Deceleration Sensor)
c. Steering Sensor
4. DIAGNOSTIC CODE FOR CAN COMMUNICATION SYSTEM
a. DTCs for CAN system are as follows: U0121/94, U0123/62, U0124/95, U0126/63
5. CAN COMMUNICATION SYSTEM WIRING DIAGRAM
HINT: The Skid Control ECU stores DTCs and performs DTC communication by receiving information from the Steering Sensor and Yaw Rate Sensor because these sensors cannot store DTCs or perform DTC communication.
6. REMARK FOR TROUBLESHOOTING
a. Trouble in the CAN bus (communication line) can be checked from the DLC3 (except when there is a wire break other than in the sub bus line of the DLC3).
b. By using the hand-held tester, DTCs for the CAN communication can be checked through the DTC ISO 9141K-Line.
c. CAN communication cannot detect the trouble on sub bus line of the DLC3 even though the DLC3 is also connected to CAN communication.