Description
CAN (Controller Area Network) is a serial communication line for real-time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent malfunction detection ability.
Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other control units during operation (not independently). In CAN communication, control units are connected with 2 communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.
DTC Logic
DTC DETECTION LOGIC
DTC | Trouble diagnosis name | DTC detection condition | Possible causes |
U0073 |
Control Module Communication Bus A Off | TCM communication blockage lasts for 2 seconds or more when turning ON the ignition switch. (Communication not established.) | Harness or connector (CAN communication line is error) |
DTC CONFIRMATION PROCEDURE
1.PREPARATION BEFORE WORK
If another "DTC CONFIRMATION PROCEDURE" occurs just before, turn ignition switch OFF and wait for at least 10 seconds, then perform the next test.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT
Is "U0073" detected?
YES >> Go to TM "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
For the diagnosis procedure, refer to LAN "Trouble Diagnosis Flow Chart".