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:
C1729 Vehicle speed signal
DTC Logic
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
Registe ...
Symptom diagnosis
Power door lock system symptoms
Symptom table
Door lock/unlock function malfunction
Note:
Before performing the diagnosis in the following table, check “WORK
FLOW”. Refer to DLK-245, "Work
Flow".
Check that vehicle is under the condition shown in “conditions of ...
P1550 Battery current sensor
DTC Logic
DTC DETECTION LOGIC
DTC No.
CONSULT screen terms
(Trouble diagnosis content)
DTC detecting condition
Possible cause
P1550
BAT CURRENT SENSOR
(Battery current sensor)
The output voltage of the battery current
sensor remains within the specified
r ...
