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 CONTINUITY OF CIRCUITS BETWEEN AV CONTROL UNIT AND TCU

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

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

AV control unit		TCU		Continuity
Connector	Terminal	Connector	Terminal
M163	46	M173	12	Yes
	48		11

Check the continuity between AV control unit connector M163 and ground.

AV control unit		Ground	Continuity
Connector	Terminal
M163	46	-	No
	48

Is the inspection result normal?

YES

GO TO 2 .

Repair or replace harness or connectors.

CHECK MICROPHONE SIGNAL (AV CONTROL UNIT)

Connect TCU connector M173.
Turn ignition switch ON.

Check the signal between the terminals of AV control unit connector M163.

AV control unit connector M163		Condition	Reference value
(+)	(-)
Terminal
46	48	Speak into microphone.	Courtesy of NISSAN NORTH AMERICA, INC.

Is the inspection result normal?

YES

Replace AV control unit. Refer to Removal and Installation .

GO TO 3 .

CHECK CONTINUITY OF CIRCUITS BETWEEN TCU AND MICROPHONE

Turn ignition switch OFF.
Disconnect TCU connector M173 and microphone connector.

Check continuity between TCU connector M173 and microphone connector R22.

TCU		Microphone		Continuity
Connector	Terminal	Connector	Terminal
M173	16	R22	2	Yes
	17		1
	18		4

Check the continuity between TCU connector M173 and ground.

TCU		Ground	Continuity
Connector	Terminal
M173	17	-	No
	18

Is the inspection result normal?

YES

GO TO 4 .

Repair or replace harness or connectors.

CHECK VOLTAGE MICROPHONE POWER SUPPLY

Connect TCU connector M173.
Turn ignition switch ON.
Check the voltage between TCU connector M173 and ground.

TCU

Ground

Voltage

(Approx.)

Connector

Terminal

M173

(-)

5.0 V

Is the inspection result normal?

YES

GO TO 5 .

Replace TCU. Refer to Removal and Installation .

CHECK MICROPHONE SIGNAL (TCU)

Turn ignition switch OFF.
Connect microphone connector.
Turn ignition switch ON.

Check the signal between the terminals of TCU connector M173.

TCU connector M173		Condition	Reference value
(+)	(-)
Terminal
17	16	Speak into microphone.	Courtesy of NISSAN NORTH AMERICA, INC.

Is the inspection result normal?

YES

Replace TCU. Refer to Removal and Installation .

Replace microphone. Refer to Removal and Installation .