Diagnosis Procedure

WARNING: This page is about a different car, the 2018 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.

CHECK CIRCUIT CONTINUITY BETWEEN TCU AND AV CONTROL UNIT

Turn ignition switch OFF.
Disconnect TCU connector M173 and AV control unit connector M163.

Check continuity between TCU connector M173 and AV control unit connector M163.

TCU		AV control unit		Continuity
Connector	Terminals	Connector	Terminals
M173	31	M163	39	Yes
	32		40

Check continuity between TCU connector M173 and ground.

TCU		Ground	Continuity
Connector	Terminals
M173	31		No
	32

Is the inspection result normal?

YES

GO TO 2 .

Repair harness or connector.

CHECK AUDIO SIGNAL

Connect TCU connector M173 and AV control unit connector M163.
Turn ignition switch ON.

Check signal between TCU connector M173 terminals.

TCU connector M173		Condition	Reference value
Terminal	Terminal
(+)	(-)
31	32	When inputting interior sound	Courtesy of NISSAN NORTH AMERICA, INC.

Is the inspection result normal?

YES

Replace AV control unit. Refer to Removal and Installation .

Replace TCU. Refer to Removal and Installation .