CAN Bus Line

CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: CAN Bus Line

CAN Bus Line

DESCRIPTION

When any DTC for the CAN communication system is output, first measure the resistance between the terminals of the DLC3 to specify the trouble area, and check that there is no short in the CAN main wire, between the main wire, and +B or GND.

WIRING DIAGRAM









INSPECTION PROCEDURE
NOTICE:
- Turn the ignition switch off before measuring the resistances of CAN bus main wires and CAN bus branch wires.
- 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 any 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. This communication will cause the resistance value to change.

PROCEDURE

1. CHECK CAN BUS WIRE (MAIN WIRE FOR DISCONNECTION, CAN BUS LINES FOR SHORT CIRCUIT)





(a) Turn the ignition switch off.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






C -- CHECK CAN BUS LINES FOR SHORT CIRCUIT
B -- CHECK OPEN IN CAN MAIN BUS LINE
A -- Continue to next step.
2. CHECK FOR SHORT TO B+ IN CAN BUS WIRE





(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- CHECK CAN BUS LINE FOR SHORT TO +B
OK -- Continue to next step.
3. CHECK FOR SHORT TO GND IN CAN BUS WIRE





(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- CHECK CAN BUS LINE FOR SHORT TO GND
OK -- GO TO HOW TO PROCEED WITH TROUBLESHOOTING