Symptom Related Diagnostic Procedures

TROUBLE DIAGNOSIS


Symptom When Error Occurs in CAN Communication System

In CAN communication system, multiple units mutually transmit and receive signals. Each unit cannot transmit and receive signals if any error occurs on CAN communication line. Under this condition, multiple control units related to the root cause malfunction or go into fail-safe mode.

ERROR EXAMPLE

NOTE:
- Each vehicle differs in symptom of each unit under fail-safe mode and CAN communication line wiring.
- Abbreviation List for the unit abbreviation.

Example: TCM branch line open circuit











Example: Data link connector branch line open circuit











NOTE:
- When data link connector branch line is open, transmission and reception of CAN communication signals are not affected. Therefore, no symptoms occur. However, be sure to repair malfunctioning circuit.
- The model (all units on CAN communication system are DIAG on CAN) cannot perform CAN diagnosis with
CONSULT-III if the following error occurs. The error is judged by the symptom.






Example: Main Line Between Data Link Connector and ABS Actuator and Electric Unit (Control Unit) Open Circuit











Example: CAN-H, CAN-L Harness Short Circuit