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:

Increasing fuel economy
Keep your engine tuned up. Follow the recommended scheduled maintenance. Keep the tires inflated to the correct pressure. Low tire pressure increases tire wear and lowers fuel economy. Keep the wheels in correct alignment. Improper alignment increases tire wear and lowers fuel eco ...

Tire Pressure Monitoring System (TPMS)
This vehicle is equipped with the Tire Pressure Monitoring System (TPMS). It monitors tire pressure of all tires except the spare. When the low tire pressure warning light is lit, and the CHECK TIRE PRES warning message is displayed in the odometer, one or more of your tires is significantly u ...

Diagnosis system (bcm) (without intelligent key system)
Common item COMMON ITEM : CONSULT Function (BCM - COMMON ITEM) APPLICATION ITEM CONSULT performs the following functions via CAN communication with BCM. Direct Diagnostic Mode Description ECU identification The BCM part number is displayed. Self Diagnostic Result ...

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