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:
Diagnosis system (EPS control unit)
CONSULT Function
FUNCTION
CONSULT can display each diagnostic item using the diagnostic
test modes shown following.
Diagnostic test mode
Function
ECU identification
The part number stored in the control unit can be read.
Self diagnostic result
Self-diagnostic r ...
Structure and operation
Positive Crankcase Ventilation
This system returns blow-by gas to the intake manifold.
The positive crankcase ventilation (PCV) valve is provided to conduct crankcase
blow-by gas to the intake
manifold.
During partial throttle operation of the engine, the intake manifold sucks the
bl ...
Ecu diagnosis information
BCM
Reference value
Note:
The signal tech ii tool (j-50190) can be used to perform the following
functions. Refer to the signal tech ii
user guide for additional information.
Activate and display tpms transmitter ids
Display tire pressure reported by the tpms transmitter
Read TPMS DTCs ...
