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:
P0181 FTT Sensor
DTC Logic
DTC DETECTION LOGIC
DTC No.
CONSULT screen terms
(Trouble diagnosis content)
DTC detecting condition
Possible cause
P0181
FTT SENSOR
(Fuel temperature sensor ″A″
circuit range/performance)
A)
Rationally incorrect voltage from the
...
Abs 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 ABS actuator and electric unit
(control unit) for damage, bend
and loose connection (unit side and connector side).
...
Front suspension assembly
Inspection
COMPONENT PART
Check the mounting conditions (looseness, backlash) of each component. Verify
the component conditions
(wear, damage) are normal.
Ball Joint Axial End Play
Set the front wheels in a straight-ahead position.
Hold the axle side of the transverse link, and check th ...
