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 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. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition | Possible cause |
U1001 | CAN COMM CIRCUIT (CAN communication circuit) | 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 1st trip DTC detected? YES >> Proceed to EC-169, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
Perform the trouble diagnosis for CAN communication system. Refer to LAN-16, "Trouble Diagnosis Flow Chart".
DTC/Circuit diagnosis
U0073 COMMUNICATION BUS A OFF
DTC Logic
DTC DETECTION LOGIC
DTC
CONSULT screen terms
(Trouble diagnosis content)
DTC detection condition
Possible causes
U0073
COMM BUS A OFF
(Control Module Communication
Bus A Off)
TCM communication blockage lasts for 2 sec ...
Diagnosis system (bcm) (with intelligent key system)
Common item
Common item : consult function (bcm - common item)
APPLICATION ITEM
CONSULT performs the following functions via CAN communication with BCM.
SYSTEM APPLICATION
BCM can perform the following functions.
Wiper
Wiper : consult function (bcm - wiper)
DATA MONITOR
ACTIVE TES ...
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”,
used along
with a front seat belt, helps to reduce the risk or severity of injury to the
driver and front passenger for certain
types of collision. Information necessary to service the system ...