Open in One Side of CAN Branch Line

CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Open in One Side of CAN Branch Line

Open in One Side of CAN Branch Line

DESCRIPTION

If 2 or more ECUs and/or sensors do not appear on the Techstream "CAN Bus Check" screen via the CAN VIM, one side of the CAN branch wire may be open. (one side of the CAN-H [branch wire] / CANL [branch wire] of the ECU and/or sensor is open.)






WIRING DIAGRAM





INSPECTION PROCEDURE
NOTICE:
- Turn the ignition switch off before measuring the resistances of the CAN main wire and the CAN branch wire.
- After the ignition switch is turned off, check that the key reminder warning system is not in operation.
- Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors. If doors need to be opened in order to check connectors, open the doors and leave them open.
HINT: Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.
HINT:
- The following is the troubleshooting procedure of an open in either CANH or CANL of the ECU A (SENSOR A).
- Perform the following inspection for the ECUs (sensors) which are not displayed on the Techstream. If malfunctions cannot be identified, then perform the following inspection for the ECUs (sensors) connected to CAN communication.

PROCEDURE

1. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (SKID CONTROL ECU)




(a) Disconnect the skid control ECU connector.
(b) Select "CAN Bus Check" on the Techstream via the CAN VIM Diagnosis System.
Result:






B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (YAW RATE SENSOR)
A -- Continue to next step.
2. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (SKID CONTROL ECU BRANCH WIRE)




(a) Measure the resistance.
Standard resistance.:






NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO SKID CONTROL ECU (CAN-H, CAN-L)
OK -- REPLACE MASTER CYLINDER SOLENOID
3. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (YAW RATE SENSOR)




(a) Disconnect the yaw rate sensor connector.
(b) Select "CAN Bus Check" on the Techstream via the CAN VIM Diagnosis System.
Result:






B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (STEERING ANGLE SENSOR BRANCH WIRE)
A -- Continue to next step.
4. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (YAW RATE SENSOR BRANCH WIRE)




(a) Measure the resistance.
Standard resistance.:






NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO YAW RATE SENSOR (CAN-H, CAN-L)
OK -- REPLACE YAW RATE SENSOR
5. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (STEERING ANGLE SENSOR BRANCH WIRE)




(a) Disconnect the steering angle sensor connector.
(b) Measure the resistance.
Standard resistance.:






NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO STEERING ANGLE SENSOR (CAN-H, CAN-L)
OK -- REPLACE STEERING ANGLE SENSOR