Audio, Visual & Navigation System (Base Audio Without Navigation): Overview

Component Description

Part name	Description
AV control unit	It is the master unit of the MULTI AV system, and it is connected to each control unit by communication. It operates each system according to communication signals from the AV control unit. The AV control unit includes the audio, rear view monitor, USB connection and vehicle information functions. It is connected to ECM and unified meter and A/C amp. via CAN communication to obtain necessary information for the vehicle information function. It is connected to BCM via CAN communication transmitting/receiving for the vehicle settings function. It inputs the illumination signals that are required for the display dimming control. It inputs the signals for driving status recognition (vehicle speed, reverse and parking brake). Camera power supply is transmitted to rear view camera.
Display unit	Display image is controlled by the serial communication from AV control unit. It receives the power (signal VCC and inverter VCC) from the AV control unit and operates. RGB image signal is input from AV control unit (RGB, RGB area and RGB synchronizing). Composite image signal (camera image) is input from AV control unit. Synchronizing signal (HP, VP) is output to AV control unit.
Front door speaker	Outputs sound signal from AV control unit. Outputs high, mid and low range sounds.
Rear door speaker	Outputs sound signal from AV control unit. Outputs high, mid and low range sounds.
Front squawker	Outputs sound signal from AV control unit. Outputs mid range sounds.
Multifunction switch	Operation panel is equipped with the centralized switch where audio, etc. operations are integrated. Connected with preset switch via cable, and operation signal is transmitted to AV control unit via AV communication.
Preset switch	Operation panel is equipped with the centralized switch where audio and air conditioner, etc. operations are integrated. Connected with multifunction switch via cable, and operation signal is transmitted to AV control unit via AV communication. The disk ejection operating signal is performed by hardwire.
Rear view camera	Camera power supply is input from AV control unit. The image of vehicle rear view is transmitted to AV control unit.
Steering switch	Operations for audio is possible. Steering switch signal (operation signal) is output to AV control unit.
USB connector	Sound signal of USB input is transmitted to AV control unit.
Antenna base	An antenna base integrated with radio antenna amp. and satellite radio antenna is adopted. ANTENNA AMP. Radio signal received by rod antenna is amplified and transmitted to AV control unit. Power (antenna amp. ON signal) is supplied from AV control unit. SATELLITE RADIO ANTENNA Receives the satellite radio waves and outputs it to satellite radio tuner.
Satellite radio tuner	Inputs the satellite radio signal from satellite radio antenna and outputs the sound signal to the AV control unit. It is controlled with the AV control unit and serial communication (communication signal and request signal).
TEL adapter unit	Inputs the TEL voice signal from TEL antenna and outputs it to the AV control unit. It is connected with the AV control unit via AV communication and controlled with the AV control unit.
TEL antenna	Receives the TEL voice signal and outputs it to the TEL adapter unit.

Scheme 1

Scheme 1: MULTI AV SYSTEM: System Diagram

Note. Flash audio is not used. The name MULTIFUNCTION SWITCH indicates the integration of PRESET SWITCH and MULTIFUNCTION SWITCH virtually. An antenna base integrated with radio antenna and satellite radio antenna is adopted.

Scheme 2

MULTI AV SYSTEM: System Description

Multi AV system means that the following systems are integrated.

FUNCTION NAME
Audio function
Hands-free phone function (1)
Rear view monitor function
Vehicle information function
(1) With Hands-free phone system

(1)	With Hands-free phone system

Description

The trouble diagnosis function has a self-diagnosis mode for conducting trouble diagnosis automatically and a confirmation/adjustment mode for operating manually.
Self-diagnosis mode performs the AV control unit diagnosis and the connection diagnosis between each of the units that make up the system, and it indicates the results to the display unit.
The confirmation/adjustment mode allows the technician to check, modify or adjust the vehicle signals and set values, as well as to monitor the system error records and system communication status. The checking, modifying or adjusting generally require human intervention and judgment (the system cannot make judgment automatically).

ECU IDENTIFICATION

The part number of AV control unit is displayed.

CONFIGURATION (AV CONTROL UNIT): Description

Since vehicle specifications are not included in the AV control unit after replacement, it is required to write vehicle specifications with CONSULT.
The AV control unit configuration includes functions as follows.

Function		Description
Read/Write Configuration	Before Replace ECU	Allows the reading of vehicle specification written in AV control unit to store the specification in CONSULT.
Read/Write Configuration	After Replace ECU	Allows the writing of the vehicle information stored in CONSULT into the AV control unit.
Manual Configuration		Allows the writing of the vehicle specification into the AV control unit by hand.

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

CAN Communication Signal Chart. Refer to " CAN SYSTEM SPECIFICATION CHART ".

U1300 is indicated when malfunction occurs in communication signal of multi AV system. Indicated simultaneously, without fail, with the malfunction of control units connected to AV control unit with communication line. Determine the possible malfunction cause from the table below.

Transmit the image displayed with AV control unit with RGB signal to the display unit.

Scheme 3

Scheme 3: Diagnosis Procedure

CHECK CONTINUITY RGB (R: RED) SIGNAL CIRCUIT Turn ignition switch OFF. Disconnect display unit connector and AV control unit connector. Check continuity between display unit harness connector and AV control unit harness connector. Display unit AV control unit Continuity Connector Terminal Connector Terminal M194 17 M202 43 Existed Check continuity between display unit harness connector and ground. Display unit Ground Continuity Connector Terminal M194 17 Not existed Is inspection result normal? YES: GO TO 2. NO: Repair harness or connector.
CHECK RGB (R: RED) SIGNAL Connect display unit connector and AV control unit connector. Turn ignition switch ON. Check signal between display unit harness connector and ground. (+) (-) Condition Reference value Display unit Connector Terminal M194 17 Ground Start confirmation/adjustment mode, and then display color bar by selecting "Color Spectrum Bar" on DISPLAY DIAGNOSIS screen. Is inspection result normal? YES: Replace display unit. Refer to " «EXPLODED VIEW»(ref-617059-S40854432482014052000000) ". NO: Replace AV control unit. Refer to " «EXPLODED VIEW»(ref-617059-S08769394752014052000000) ".

Transmit the image displayed with AV control unit with RGB signal to the display unit.

Transmit the RGB synchronizing signal to the display unit so as to synchronize the RGB image displayed with AV control unit.

Transmits the display area of RGB image displayed by AV control unit with RGB area (YS) signal to display unit.

AV control unit that inputs the camera image signal transmits the composite image signal to the display unit.

In composite image (camera image), transmit the vertical synchronizing (VP) signal and horizontal synchronizing (HP) signal from display unit to AV control unit so as to synchronize the RGB images displayed with AV control unit such as the image quality adjusting menu, etc.

The eject signal is output to AV control unit when the eject switch of multifunction switch is pressed.

Supply power from TEL adapter unit to microphone. The microphone transmits the sound/voice to the microphone.

AV control unit outputs camera power supply to rear view camera and inputs rear view camera image signal from rear view camera when the reverse signal is input.
The AV control unit that inputs the camera image signal transmits the camera image signal to the display unit.

Satellite radio tuner and AV control unit are connected with a serial communication. They transmit the operation signal from AV control unit to satellite radio tuner, and transmit the display signal from satellite radio tuner to AV control unit.

Request signal transmits the signal to recognize the connection of satellite radio tuner from satellite radio tuner to AV control unit.

WITH HANDS-FREE PHONE SYSTEM: Description

Transmits the steering switch signal to AV control unit.

WITHOUT HANDS-FREE PHONE SYSTEM: Description

Transmits the steering switch signal to AV control unit.

OPERATION

Symptoms	Check items	Possible malfunction location/Action to take
Multifunction switch and preset switch operation does not work.	All switches cannot be operated. "MULTI AV" is displayed on system selection screen when the CONSULT is started.	Multifunction switch power supply and ground circuit. AV communication circuit between AV control unit and multifunction switch. Perform "Self diagnosis Result" of "MULTI AV" with CONSULT. Refer to " CONSULT FUNCTION (MULTI AV) ".
	All switches cannot be operated. "MULTI AV" is not displayed on system selection screen when the CONSULT is initialized.	AV control unit power supply and ground circuit malfunction. Refer to " AV CONTROL UNIT: DIAGNOSIS PROCEDURE ".
	Only specified switch cannot be operated.	Multifunction switch or preset switch malfunction. Perform multifunction switch and preset switch self-diagnosis function. Refer to " ON BOARD DIAGNOSIS FUNCTION ".
Fuel economy display, vehicle setting operation is abnormal.	There is malfunction in the CONSULT self-diagnosis result. Refer to " CONSULT FUNCTION (MULTI AV) ".	Perform detected DTC diagnosis. Refer to " DTC INDEX ".
	There is no malfunction in the self-diagnosis results. Refer to " CONSULT FUNCTION (MULTI AV) ".	Ignition signal circuit malfunction. (AV control unit)

BASIC OPERATIONS

Symptom	Possible cause	Possible solution
No image is displayed.	The brightness is at the lowest setting.	Adjust the brightness of the display.
	The systems in the video mode.	Press "DISC-AUX" to change the mode.
	The display is turned off.	Press "ILLUM (SUN/MOON) OFF" to turn on the display.
The screen is too dim. The movement is slow.	The temperature in the interior of the vehicle is low.	Wait until the interior of the vehicle has warmed up.
Some pixels in the display are darker or brighter than others.	This condition is an inherent characteristic of liquid crystal displays.	This is not a malfunction.
Some menu items cannot be selected.	Some menu items become unavailable while the vehicle is driven.	Park the vehicle in a safe location, and then operate the multi AV system.

Audio, Visual & Navigation System (Base Audio Without Navigation): Overview Infiniti QX50 I