Nissan Sentra Service Manual: DTC/Circuit diagnosis
U0073 COMMUNICATION BUS A OFF
DTC Logic
DTC DETECTION LOGIC
| DTC | CONSULT screen terms (Trouble diagnosis content) | DTC detection condition | Possible causes |
| U0073 | COMM BUS A OFF (Control Module Communication Bus A Off) | TCM communication blockage lasts for 2 seconds or more when turning ON the ignition switch. (Communication not established.) | Harness or connector (CAN communication line is error) |
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.PERFORM DTC CONFIRMATION PROCEDURE
- Start the engine and wait for at least 5 seconds.
- Check the DTC.
Is “U0073” detected? YES >> Go to TM-152, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
For the diagnosis procedure, refer to LAN-16, "Trouble Diagnosis Flow Chart".
U0100 LOST COMMUNICATION (ECM A)
DTC Logic
DTC DETECTION LOGIC
| DTC | CONSULT screen terms [Trouble diagnosis content] | DTC detection condition | Possible causes |
| U0100 | LOST COMM (ECM A) [Lost Communication With ECM/PCM A] | When the ignition switch is ON, TCM is unable to receive the CAN communications signal from ECM continuously for 2 seconds or more. |
|
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.PERFORM DTC CONFIRMATION PROCEDURE
- Start the engine and wait for at least 5 seconds.
- Check the DTC.
Is “U0100” detected? YES >> Go to TM-153, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
For the diagnosis procedure, refer to LAN-16, "Trouble Diagnosis Flow Chart".
Basic inspection
DIAGNOSIS AND REPAIR WORK FLOW
Work Flow
NOTE:
“DTC” includes DTC at the 1st trip.
1.OBTAIN INFORMATION ABOUT SYMPTOM
Refer to TM-140, "Diagnostic Work Sheet" and interview t ...
U0140 Lost communication (BCM)
DTC Logic
DTC DETECTION LOGIC
DTC
CONSULT screen terms
[Trouble diagnosis content]
DTC detection condition
Possible causes
U0140
LOST COMM (BCM)
[Lost Communication ...
Other materials:
Intake valve timing control
INTAKE VALVE TIMING CONTROL : System Description
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
Sensor
Input signal to ECM
ECM function
Actuator
Crankshaft position sensor (POS)
Engine speed and piston position
Intake valve timing
control
Intake valve timing con ...
Engine control system
Symptom Table
SYSTEM — BASIC ENGINE CONTROL SYSTEM
1 - 6: The numbers refer to the order of inspection.
(continued on next table)
SYSTEM — ENGINE MECHANICAL & OTHER
1 - 6: The numbers refer to the order of inspection. ...
Dtc/circuit diagnosis
U1000 can comm circuit
DTC Logic
DTC DETECTION LOGIC
CONSULT Display
DTC Detection Condition
Possible Cause
CAN COMM CIRCUIT
[U1000]
AV control unit is not transmitting or receiving
CAN communication signal for 2 seconds or
more.
CAN communication system.
...
