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:
M&A branch line circuit
Diagnosis procedure
1.Check connector
Turn the ignition switch off.
Disconnect the battery cable from the negative terminal.
Check the terminals and connectors of the combination meter for damage,
bend and loose connection
(unit side and connector side).
Is the inspection result nor ...
Work Flow
STEP
DESCRIPTION
STEP 1
Get detailed information about the conditions and the
environment when the incident occurred.
The following are key pieces of information required to make a good
analysis:
WHAT
Vehicle Model, Engine, Transmission/Transaxle and ...
Diagnosis description : malfunction indicator lamp (MIL)
When emission-related ECU detects a malfunction in the emission
control systems components and/or the powertrain control components
(which affect vehicle emissions), it turns on/blinks MIL to
inform the driver that a malfunction has been detected.
The MIL illuminates when ignition switch is t ...
