Nissan Sentra Service Manual: U1000 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 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 | CONSULT screen terms (Trouble diagnosis content) | DTC detection condition | Possible causes |
| U1000 | CAN COMM CIRCUIT (CAN Communication Line) | When the ignition switch is ON, TCM cannot send the CAN communication signal continuously for 2 seconds or more. | Harness or connector (CAN communication line is open or shorted) |
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.CHECK DTC DETECTION
With CONSULT
- Start the engine and wait for at least 5 seconds.
- Check the DTC.
Is “U1000” detected? YES >> Go to TM-158, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
For the diagnosis procedure, refer to LAN-16, "Trouble Diagnosis Flow Chart".
U0155 Lost communication (IPC)
DTC Logic
DTC DETECTION LOGIC
DTC
CONSULT screen terms
[Trouble diagnosis content]
DTC detection condition
Possible causes
U0155
LOST COMM (IPC)
[Lost Communication ...
U1117 Lost communication (ABS)
DTC Logic
DTC DETECTION LOGIC
DTC
CONSULT screen terms
[Trouble diagnosis content]
DTC detection condition
Possible causes
U1117
LOST COMM (ABS)
[Lost Communication ...
Other materials:
Main power supply and ground circuit
Diagnosis Procedure
1.CHECK TCM POWER CIRCUIT (PART 1)
Turn ignition switch OFF.
Disconnect TCM connector.
Check voltage between TCM harness connector terminals and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> GO TO 4.
2.CHECK TCM POWER CIRCUIT (PAR ...
Periodic maintenance
M/T OIL
Inspection
OIL LEAKAGE
Make sure that gear oil is not leaking from transaxle or around it.
OIL LEVEL
Remove filler plug (1) and gasket from transaxle case.
Check the oil level from filler plug mounting hole as shown.
CAUTION:
Do not start engine while checking oil level.
Se ...
System description
Component parts
CVT CONTROL SYSTEM
CVT CONTROL SYSTEM : Component Parts Location
No.
Component
Function
1
ECM
Mainly transmits the following signal to TCM via CAN
communication.
Engine and CVT integrated control signal
NOTE:
General term for the c ...
