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:
Standardized relay
Description
Normal open, normal closed and mixed type relays
Relays can mainly be divided into three types: normal open, normal closed and
mixed type relays.
Type of standardized relays
...
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 ...
ABS Warning lamp
Component Function Check
1.CHECK ABS WARNING LAMP FUNCTION
Check that ABS warning lamp in combination meter turns ON for
approximately 2 seconds after ignition switch
is turned ON.
Is the inspection result normal?
YES >> Inspection End.
NO >> Proceed to diagnosis procedure. ...
