Toyota Sequoia (2005). Manual - part 541

DID9M–01

I28302

Example :

Head

Capstan

Pinch Roller

I28257

–

DIAGNOSTICS

AUDIO SYSTEM

DI–1959

2153

SYSTEM DESCRIPTION

1.

COMPACT DISC PLAYER

Compact Disc (hereafter called ”CD”) Players use a laser beam pick–up to read the digital signals recorded
on the CD and reproduce analog signals of the music, etc. 4.7 in. (12 cm) and 3.2 in. (8 cm) discs are available
for the CD player.
HINT:
Never disassemble or apply oil to any part of the player unit. Do not insert any object other than a disc, into
the CD player.
NOTICE:
CD players use an invisible laser beam which could cause hazardous radiation exposure. Be sure
to operate the player correctly as instructed.

2.

MAINTENANCE
Tape Player / Head Cleaning:

(a)

Raise the cassette door with your finger.
Using a pencil or similar object, push in the guide.

(b)

Using a cleaning pen or cotton applicator soaked in clean-
er, clean the head surface, pinch rollers and capstans.

3.

MAINTENANCE
CD Player / Disc Cleaning:

If the disc gets dirty, clean the disc by wiping the surface from
the center to outside in a radial directions with a soft cloth.
NOTICE:
Do not use a conventional record cleaner or anti–static pre-
servative.

I28193

AVC–LAN

Stereo Component 
Amplifier Assy

Radio Receiver Assy 
(Resistor 60 to 80 

Ω

)

Example :

DI–1960

–

DIAGNOSTICS

AUDIO SYSTEM

2154

4.

OUTLINE OF AVC–LAN

(a)

What is AVC–LAN?
AVC–LAN is the abbreviation for Audio Visual Communication–Local Area Network. This is a unified
standard co–developed by 6 audio manufacturers associated with Toyota Motor Corporation.
The unified standard includes signals, such as audio, visual and signals for switch indication and com-
munication.

(b)

Objectives
Recently development in car audio systems has been rapid and functions have been changed drasti-
cally. The conventional system has been switched to a multi–media type such as a navigation system.
At the same time customers wants to upgrade their audio systems. This is the factor that lies behind
this standardization.
The concrete objectives are explained below.
(1)

When products by different manufacturers were combined together, malfunctions such as sound
failure occurred. This problem can be solved by standardization of signals.

(2)

Various types of after market products are available.

(3)

In general, a new product developed by a particular manufacturer could not be used due to a
lack of compatibility with other manufacturer’s products. By developing this new standard, users
can enjoy a range of compatible products from different manufacturers.

HINT:

When +B short or GND short is detected in the AVC–LAN circuit, communication stops, and the audio
system will not function.

When the audio system is not equipped with a navigation system, the audio head unit is the master
unit. When the audio system is equipped with a navigation system, the multi–display is the master unit.

The radio receiver assy is equipped with a resistor (60 to 80 

Ω

) for communication.

All car audio systems using an AVC–LAN circuit have a diagnostic function.

Each unit has its own specified number called a physical address (three–digit number). Numbers are
also allotted to each function, which are called logical addresses (two–digit number).

5.

COMMUNICATION SYSTEM

(a)

Components in the audio system communicate with each other through the AVC–LAN. (Radio receiver
with CD changer control function)

(b)

When a short circuit or circuit breakdown occurs in the AVC–LAN circuit, the audio system does not
operate normally due to the communication cutoff.

I28736

Main AVC–LAN:

(*1)

(*2, 3)

Multi–display
Controller (*2)
Rear Seat Audio
Controller (*3)

Radio
Receiver Assy

Stereo
Component
Amplifier

Sub AVC–LAN:

(*2)

(*2)

Disc
Player
Controller
(*2)

Television
Display Assy (*2)

*1: Separate Type Amplifier
*2: w/ RSE System
*3: w/ RSA System

–

DIAGNOSTICS

AUDIO SYSTEM

DI–1961

2155

6.

DIAGNOSTIC FUNCTION

(a)

The audio system has diagnostic function (The diagnostic result is displayed on the LCD of the radio
receiver assy). (Radio receiver with CD changer control function)

(b)

The component code (physical address), or three–digit number (in hexadecimal) is set for each com-
ponent comprising AVC–LAN.

(c)

The logical address, or two–digit number (in hexadecimal) is set for each function and component unit
in each component.

DID9N–01

Vehicle brought into a workshop

3. Check the diagnostic trouble codes

DTC is not output (Go to step 5)

4. Diagnostic trouble code chart.

Go to step 6

6. Circuit inspection and part inspection

8. Perform confirmation test

END

Items inside

are titles of pages in this manual,

with the page number in the bottom portion. See
the pages for detailed explanations.

P. 

DI–1974

P. 

DI–1990

 – 

DI–2042

P. 

DI–1979

1. Customer problem analysis

P. 

DI–1963

(a) Interview and confirm the trouble.
    (1) Confirm the condition of the trouble.

(a) Basic inspection
    (1) Check the battery voltage.

2. Basic inspection.

Standard: 11 to 14 V

(b) Check the power supply to the radio receiver assy.
    (1) Turn the ignition switch to the ACC position.
    (2) Check whether or not the display appears on the radio receiver assy.

Display does not appear (Proceed to problem
symptom table)

Display appears

DTC is output

5. Problem symptoms table

P. 

DI–1967

7. Identification of problem

P. 

DI–1967

DI–1962

–

DIAGNOSTICS

AUDIO SYSTEM

2156

HOW TO PROCEED WITH TROUBLESHOOTING