Nissan Sentra manuals

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

  1. Start the engine and wait for at least 5 seconds.
  2. 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.
  • ECM
  • 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.PERFORM DTC CONFIRMATION PROCEDURE

  1. Start the engine and wait for at least 5 seconds.
  2. 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:

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Precaution
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Dlc branch line circuit
Diagnosis Procedure 1.Check connector Turn the ignition switch off. Disconnect the battery cable from the negative terminal Check the terminals and connectors of the data link connector for damage, bend and loose connection (connector side and harness side). Is the inspection result ...

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