Open in One Side of CAN Branch Line
Open in One Side of CAN Branch LineDESCRIPTION
If 2 or more ECUs and/or sensors do not appear on the intelligent tester "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:
Step 1:
Step 2:
Step 4-5:
Step 6-7:
Step 8-9:
INSPECTION PROCEDURE
NOTE:
- 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 and light reminder warning system are 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:
- Perform the following inspection for the ECUs (sensors) which are not displayed on the intelligent tester. If malfunction cannot be identified, then perform the following inspections for the ECUs (sensors) connected to CAN communication.
- Do not remove the power steering ECU and ECM, as they are the end parts of the circuit. If removed, CAN communication will not be possible.
- The open circuit confirmation of the power steering ECU, ECM and main wire is performed in the CHECK CAN BUS LINE procedure of HOW TO PROCEED WITH TROUBLESHOOTING. This inspection only has procedures for checking for an open circuit on one side of the CAN branch wire.