05 identification of noise source 05 nhận dạng nguồn tiếng ồn

Sound signal circuit between radio receiver and stereo component amplifier Click here 5.. Mute signal circuit between radio receiver and stereo component amplifier Click here 7.. Mu

AUDIO AND VISUAL SYSTEM > IDENTIFICATION OF NOISE SOURCE

for Preparation Click here

Radio Description

1 Radio frequency band

1 Radio broadcasts use the radio frequency bands shown in the table below

● Service area

1 The service areas of AM and FM broadcasts are vastly different Sometimes an AM broadcast can be received very clearly but

an FM stereo cannot FM stereo has the smallest service area, and is prone to pick up static and other types of interference such

2 Multipath

Multipath is a type of interference created when a vehicle receives 2 radio wave signals from the same transmitter One signal

is reflected off buildings or mountains and the other signal is received directly from the transmitter

3 Fade out

Fade out is caused by objects (buildings, mountains, and other large obstacles) that deflect away part of a signal, resulting in a weaker signal when the object is between the transmitter and vehicle High frequency radio waves, such as FM broadcasts, are easily deflected by obstructions Low frequency radio waves, such as AM broadcasts, are much more difficult to deflect

● Noise problem

Technicians must have a clear understanding about each customer's noise complaint Use the following table to diagnose noise problems

AM Noise occurs when listening to an intermittent

broadcast

An identical program transmitted from multiple towers can cause noise where the signals overlap

FM Noise occurs while driving in a specified area Multipath or phasing noise resulting

from a change in FM frequency HINT:

If the noise does not match the examples above, refer to the descriptions about phasing and multipath.

AUDIO AND VISUAL SYSTEM > PROBLEM

SYMPTOMS TABLE

for Preparation Click here

HINT:

1 Before inspecting the suspected areas listed in the table below, check the fuse and relay

2 Before inspecting the suspected areas listed in the table below, check the DTCs

3 Methods used to verify the cause of the problem are listed in order of probability in the suspected area column

Audio Function:

Symptom Suspected area See page

Pressing power switch does

not turn on system

1 "Pressing Power Switch does not Turn on System" Click here

2 Radio receiver power source circuit Click here

3 AVC-LAN circuit Click here

4 Replace radio receiver Click here

Panel switch does not

function

1 Steering pad switch circuit Click here

2 AVC-LAN circuit Click here

3 Replace radio receiver Click here

1 Radio receiver power source circuit Click here

2 "No Sound can be Heard from Speakers (Audio is Mute)" Click here

3 Stereo component amplifier power source circuit Click here

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No sound can be heard from

speakers (audio is mute)

4 Sound signal circuit between radio receiver and stereo

component amplifier

Click here

5 Speaker circuit Click here

6 Mute signal circuit between radio receiver and stereo component amplifier

Click here

7 Mute signal circuit between navigation ECU and stereo component amplifier

Click here

8 Replace stereo component amplifier Click here

9 Replace radio receiver Click here

Sound cannot be heard only

from front speaker (driver

side) (Volume is too low.)

(Only with navigation

system)

1 Driver side speaker circuit Click here

2 Sound signal circuit between radio receiver and stereo

component amplifier

Click here

3 Replace stereo component amplifier Click here

4 Replace radio receiver Click here

Sound quality is bad in all

modes (Volume is too low.)

1 "Poor Sound Quality in All Modes (Low Volume)" Click here

2 Speaker circuit Click here

3 Sound signal circuit between radio receiver and stereo

component amplifier

Click here

4 Mute signal circuit between radio receiver and stereo component amplifier

Click here

5 Mute signal circuit between navigation ECU and stereo component amplifier

ASL does not function

1 Vehicle speed signal circuit between stereo component amplifier and combination meter

Click here

Sound cannot be heard or

sound quality is bad (RSE

Click here

4 Replace radio receiver Click here

5 Replace multi-display controller Click here

Abnormal noise occurs

1 "Noise occurs" Click here

2 Replace stereo component amplifier Click here

3 Replace radio receiver Click here Radio broadcast cannot be

received (poor reception)

1 "Radio Broadcast cannot be Received (Poor Reception)" Click here

Click here

CD sound skips 1 "CD Sound Skips" Click here

Cassette tape cannot be

Cassette tape cannot be

when playing tape

1 "Sound Quality is Bad Only when Playing Tape" Click here Tape is tangled due to

incorrect tape speed or

auto-reverse malfunction

1 "Tape is Tangled due to Incorrect Tape Speed or Auto- Reverse Malfunction"

Click here

Radio receiver cannot be

dimmed in night time

1 Dimmer signal circuit Click here

2 Replace radio receiver Click here Radio receiver cannot be

illuminated in night time

1 Illumination circuit Click here

2 Replace radio receiver Click here Steering Pad Switch Function:

Symptom Suspected area See page

Audio system cannot be

operated with steering pad

switch

1 Steering pad switch circuit Click here

2 Replace radio receiver Click here

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AUDIO AND VISUAL SYSTEM > TERMINALS OF ECU

for Preparation Click here

A waveform synchronized with sounds is output

A waveform synchronized with sounds is output

Turn ignition switch off →

ON

Below 1 V → Pulse generation ANT (R2-13) - GND (R2-

Power source of antenna

Radio switch ON and AM

ATX- 15) - GND

AVC-LAN

A waveform synchronized with sounds is output

A waveform synchronized with sounds is output GND (R2-20) - Body

ground

BR - Body

signal

Steering pad switch not operated

→ SEEK+ switch pushed

→ SEEK- switch pushed

→ VOL+ switch pushed

→ VOL- switch pushed

4 V or more → Below 2.5 V TX+ (R4-9) - GND (R2-20)

R-R- (R4-16) - GND

A waveform synchronized with sounds is output

R-L+ (R4-17) - GND

A waveform synchronized with sounds is output

R-L- (R4-18) - GND

A waveform synchronized with sounds is output RMUT (R4-19) - GND (R2-

Audio system is playing → Changing

Above 3.5 V → Below 1 V

ADIM (R4-20) - GND

Illumination (auto dimmer) signal

Ignition switch on, headlight dimmer switch in TAIL or ON and automatic light control sensor covered

by hand

Above 9 V

CDR+ (R3-2) - GND

A waveform synchronized with sounds is output

CDR- (R3-3) - GND

A waveform synchronized with sounds is output

CDL+ (R3-4) - GND

A waveform synchronized with sounds is output

CDL- (R3-5) - GND

A waveform synchronized with sounds is output MUTE (R3-6) - GND (R2-

Above 3.5 V → Below 1 V TX+ (R3-9) - GND (R2-20)

*1: With Navigation System

*2: With Rear Seat Entertainment System

STEREO COMPONENT AMPLIFIER (STANDARD SYSTEM)

*1: With Navigation System

*2: Without Navigation System

Symbols (Terminal No.) Wiring Color Terminal Description Condition Specification

WF2+ 4) - GND

Sound signal (Woofer

A waveform synchronized with sounds is output

WF1+ 5) - GND

Sound signal (Woofer

A waveform synchronized with sounds is output

RL+ 6) - GND

Sound signal (Rear

A waveform synchronized with sounds is output

RR+ 7) - GND

Sound signal (Rear

A waveform synchronized with sounds is output

FL+ 8) - GND

(S30-16)

Y (*1) - W-B

BR (*2) - W-B

Sound signal (Front

A waveform synchronized with sounds is output

FR+ 9) - GND

Sound signal (Front

A waveform synchronized with sounds is output +B2 (S30-10) - GND (S30-

WF2- 13) - GND

Sound signal (Front

A waveform synchronized with sounds is output

WF1- 14) - GND

Sound signal (Front

A waveform synchronized with sounds is output GND2 (S30-15) - Body

Sound signal (Rear

A waveform synchronized with sounds is output

RR- 18) - GND

Sound signal (Rear

A waveform synchronized with sounds is output

FL- 19) - GND

(S30-16)

LG (*1) - W-B R-Y (*2) - W-B

Sound signal (Front

A waveform synchronized with sounds is output

FR- 20) - GND

Sound signal (Front

A waveform synchronized with sounds is output MUTE (S29-1) - GND (S30-

A waveform synchronized with sounds is output

A waveform synchronized with sounds is output

A waveform synchronized with sounds is output

A waveform synchronized with sounds is output TX- (S29-7) - GND (S30-

AVC-LAN

Speed signal from

ACC (S29-12) - GND

Below 1 V →

10 to 14 V N-MU (S29-21) - GND

Mute signal from navigation ECU

Navigation system is changing

Above 3.5 V → Below 1 V

STEREO COMPONENT AMPLIFIER (MARK LEVINSON SYSTEM)

*1: With Navigation System

*2: Without Navigation System

FR+ 1) - GND

Sound signal (Front

A waveform synchronized with sounds is output

FL+ 2) - GND

Sound signal (Front

A waveform synchronized with sounds is output

RR+ 3) - GND

Sound signal (Rear

A waveform synchronized with sounds is output

RL+ 4) - GND

Sound signal (Rear

A waveform synchronized with sounds is output

CTF+ 5) - GND

A waveform synchronized with sounds is output

B+ (S28-7) - GND (S28-13) W - W-B Battery Always 10 to 14 V

FR- 8) - GND

Sound signal (Front

A waveform synchronized with sounds is output

A waveform synchronized with sounds is output

RR- 10) - GND

Sound signal (Rear

A waveform synchronized with sounds is output

RL- 11) - GND

Sound signal (Rear

A waveform synchronized with sounds is output

TFR+ (S27-1) - GND

Sound signal (Front

A waveform synchronized with sounds is output

TFL+ (S27-2) - GND

(S28-13)

Y (*1) - W-B

BR (*2) - W-B

Sound signal (Front

A waveform synchronized with sounds is output MTX+ (S27-5) - GND (S28-

R+ (S27-11) - GND

Sound signal from

A waveform synchronized with sounds is output

L+ (S27-12) - GND

Sound signal from

A waveform synchronized with sounds is output SPD (S27-13) - GND (S28-

Speed signal from

TFR- (S27-14) - GND

Sound signal (Front

A waveform synchronized with sounds is output

TFL- (S27-15) - GND

(S28-13)

LG (*1) - W-B R-Y (*2) - W-B

Sound signal (Front

A waveform synchronized with sounds is output MTX- (S27-18) - GND

A waveform synchronized with sounds is output

A waveform synchronized with sounds is output

AUDIO AND VISUAL SYSTEM > PRECAUTION

for Preparation Click here

Sliding Roof Control System (Standard Type) Click here

Sliding Roof Control System (Multi-panel Moon

Roof Type) Click here

Power Window Control System Click here

Power Back Door System Click here

Back Door Closer System Click here

Electrical Back Door Outside Handle System Click here

1.OBSERVE HANDLING AND OPERATIONAL PRECAUTIONS

1 Please explain to the customer that when the negative terminal is disconnected from the battery, the channel information memory of the AM / FM broadcast stations in the radio receiver is cleared If necessary, make a note of the recorded channel information before the negative terminal is disconnected, then reset the information after the negative terminal is reconnected

2 The removal / installation of the radio receiver should be performed after all the cassette tapes and audio CDs are ejected from the radio receiver

HINT:

If the cassette tapes and the audio CDs cannot be ejected due to the malfunction of the

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radio receiver, do not try to drag them out by force Bring the vehicle to the repair plant.

3 Fasten the earth bolt securely when the antenna cord is removed or installed

HINT:

Failing to fasten the earth bolt securely causes noise at the time of radio wave reception.

4 Do not touch the cone paper of the speaker

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AUDIO AND VISUAL SYSTEM > SYSTEM

DESCRIPTION

for Preparation Click here

DISC PLAYER OUTLINE

1 A compact disc player or digital versatile disc player uses a laser pickup to read digital signals recorded on compact discs (CDs) or digital versatile discs (DVDs) By converting the digital signals to analog, music and other things can be played

CAUTION:

Do not look directly at the laser pickup because the CD/DVD player uses an invisible laser beam Be sure to operate the player only as instructed

NOTICE:

1 Do not disassemble any part of the CD or DVD player

1 Do not apply oil to the CD or DVD player

1 Do not insert anything but a CD or a DVD into the CD or DVD player

audio and visual signals as well as switch and communication signals

2 Purpose:

Recently, car audio systems have rapidly developed and the functions have vastly changed The

conventional car audio system is being integrated with multi-media interfaces similar to those in navigation systems At the same time, customers are demanding higher quality from their audio systems This is merely an overview of the standardization background The specific purposes are as follows:

1 To solve sound problems, etc., caused by using components of different manufacturers through signal standardization

2 To allow each manufacturer to concentrate on developing products they do best From this,

reasonably priced products can be produced

3 The radio receiver provides resistance to make communication possible

4 The car audio system with an AVC-LAN circuit has a diagnostic function

5 Each component has a specified number (3-digit) called a physical address Each function has a number (2-digit) called a logical address

COMMUNICATION SYSTEM OUTLINE

1 Components of the audio system communicate with each other via the AVC-LAN

2 The master component of the AVC-LAN is a radio receiver with a 60 to 80 Ω resistor This is essential for communication

3 If a short circuit or open circuit occurs in the AVC-LAN circuit, communication is interrupted and the audio system will stop functioning

DIAGNOSTIC FUNCTION OUTLINE

1 The audio system has a diagnostic function (the result is indicated on the master unit)

2 A 3-digit hexadecimal component code (physical address) is allocated to each component on the LAN Using this code, the component in the diagnostic function can be displayed

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