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:
Precaution for Harness Repair
Solder the repair part, and wrap it with tape. [Twisted wire
fray
must be 110 mm (4.33 in) or less.]
Do not bypass the repair point with wire. (If it is
bypassed, the turnout
point cannot be separated and the twisted wire characteristics
are lost.)
...
U1010 Control unit (CAN)
Description
Air bag diagnosis sensor performs self-tests on key ON. If CAN communication
failure within control unit is
detected, DTC is set.
DTC Logic
DTC DETECTION LOGIC
CONSULT name
DTC
DTC detecting condition
Repair order
CAN CONTROL UNIT FAILURE
U1010
CAN ...
Uniform tire quality grading
DOT (Department of Transportation) Quality
Grades: All passenger car tires must conform to
federal safety requirements in addition to these
grades.
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 ...
