Nissan Sentra Service Manual: U0101 can comm circuit
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 |
| U0101 | LOST COMM (TCM) (Lost communication with TCM) | When ECM is not transmitting or receiving CAN communication signal of OBD (emission-related diagnosis) with TCM for 2 seconds or more. | CAN communication line between TCM and ECM |
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
- Turn ignition switch ON and wait at least 3 seconds.
- Check DTC.
Is DTC detected? YES >> Proceed to EC-168, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
Perform the trouble diagnosis for CAN communication system. Refer to LAN-16, "Trouble Diagnosis Flow Chart".
Power supply and ground circuit
Diagnosis Procedure
1.CHECK FUSE
Check that the following fuse is not fusing.
Is the fuse fusing?
YES >> Replace the fuse after repairing the applicable circuit.
NO >> GO TO 2.
...
U1001 can comm circuit
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 excellen ...
Other materials:
Push-Button Ignition Switch (if so equipped)
WARNINGDo not operate the push-button ignition
switch while driving the vehicle except in
an emergency. (The engine will stop when
the ignition switch is pushed 3 consecutive
times in quick succession or the ignition
switch is pushed and held for more
than 2 seconds.) If ...
Daytime light system inoperative
Description
The daytime light system is inoperative even though the combination switch
(lighting and turn signal switch)
and parking brake switch are in the normal setting, also whenever engine is
operating.
Diagnosis procedure
1.Check daytime light operation
Perform bcm(headlamp) daytim ...
Precaution for work
When removing or disassembling each component, be careful not to damage
or deform it. If a component
may be subject to interference, be sure to protect it with a shop cloth.
When removing (disengaging) components with a screwdriver or similar
tool, be sure to wrap the component
with a ...
