Nissan Sentra B18 (2020-2025) Service Manual: U0073-00 Control Module Comm Bus a Off

Nissan Sentra B18 (2020-2025) Service Manual / Electrical & Power Control / Power Control System :: Ipdm E/r / Dtc/circuit Diagnosis / U0073-00 Control Module Comm Bus a Off

Dtc Description

DTC Description

CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-Nissan Sentra vehicle multiplex communication line with high data communication speed and excellent error detection ability. Modern Nissan Sentra vehicle is equipped with many electronic control unit, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN-High line, CAN-Low line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.

DTC DETECTION LOGIC

DTC No.	CONSULT screen items (Trouble diagnosis content)		DTC detection condition
U0073-00	Control module comm Bus A Off (Control module communication bus A off)	[NO SUBTYPE INFO]	Diagnosis condition	When ignition switch is ON
			Signal (terminal)	CAN communication signal
			Threshold	When IPDM E/R cannot communicate CAN communication signal
			Diagnosis delay time	2 seconds or more

POSSIBLE CAUSE

CAN communication system

FAIL-SAFE

When CAN communication with the ECM and BCM is impossible, the IPDM E/R performs fail-safe control. After CAN communication recovers normally, it also returns to normal control.

Dtc Confirmation Procedure

DTC Confirmation Procedure

PERFORM DTC CONFIRMATION PROCEDURE
1. CONSULT
  1. Ignition switch ON and wait for 2 seconds or more.
  2. Select “Self Diagnostic Result” mode of “IPDM E/R”.
Is DTC detected?
YES>>
Refer to DTC Diagnosis Procedure.
NO>>
To check malfunction symptom before repair: Refer to Intermittent Incident.
NO>>
Confirmation after repair: Inspection End.

Dtc Diagnosis Procedure

DTC Diagnosis Procedure

CHECK CAN COMMUNICATION SYSTEM
1. Perform trouble diagnosis for CAN communication system. Refer to Trouble Diagnosis Flow Chart.
>>
Inspection End.

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