Description
CAN (Controller Area Network) is a serial communication line for real time application. It is an onvehicle multiplex communication line with high data communication speed and excellent error 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 independent). 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 No. | Trouble diagnosis name | DTC detecting condition | Possible cause |
U1001 | CAN communication line | When ECM is not transmitting or receiving CAN communication signal other than OBD (emission related diagnosis) for 2 seconds or more. | Harness or connectors (CAN communication line is open or shorted) |
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
Is DTC detected?
YES >> EC, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
Go to LAN, "Trouble Diagnosis Flow Chart".