1986 TOYOTA LAND CRUISER audio

AC1KN-05
I15824
Cowl Side Trim
Front Door Scuff PlateCenter Pillar Garnish
Rear Door Scuff plate
Console Upper Panel
Lower Center Cluster
Finish Panel
Audio Amplifier
Front Console Box Rear Heater Unit
Rear Console
End Panel
Cooler Bracket Rear Heater Duct
Rear Console Box
- AIR CONDITIONINGREAR HEATER UNIT
AC-45
2770 Author
: Date
:
2004 LAND CRUISER (RM1071U)
REAR HEATER UNIT
COMPONENTS

BE2E8-01
30 kHz 300 kHz 3 MHz 30 MHz 300 MHz
LF MF HF VHF
AM FM
Frequency modulation Frequency
Designation
Radio wave
Modulation Amplitude modulation
BE2818
FM (Stereo)
FM (Monaural)
AM
BE2819
Fading:lonosphere BE-124
- BODY ELECTRICALAUDIO SYSTEM
2497 Author
: Date
:
2004 LAND CRUISER (RM1071U)
AUDIO SYSTEM
DESCRIPTION
1. RADIO WAVE BAND
The radio wave bands used in radio broadcasting are as follows:
LF: Low Frequency
MF: Medium Frequency
HF: High Frequency
VHF: Very High Frequency
2. SERVICE AREA
There are great differences in the size of the service area for AM
and FM monaural. Sometimes FM stereo broadcasts cannot be
received even through AM can be received in very clearly.
Not only does FM stereo have the smallest service area, but it
also picks up static and other types of interference (ºnoiseº)
easily.
3. RECEPTION PROBLEMS
Besides the problem of static, there are also the problems
called ºfadingº, ºmultipathº and ºfade outº. These problems are
caused not by electrical noise but by the nature of the radio
waves themselves.
(1) Fading
Besides electrical interference, AM broadcasts are
also susceptible to other types of interference, es-
pecially at night. This is because AM radio waves
bounce off the ionosphere at night. These radio
waves then interfere with the signals from the same
transmitter that reach the vehicle's antenna directly.
This type of interference is called ºfadingº.

BE2820
Multipath
BE2821
Fade Out
Noise occurs at a specific place. Strong possibility of foreign noise.
There is a possibility that the same program is broadcasted
from different local stations, and that might be listening a
program from other station.
Strong possibility of the beat from a distant broadcasting.
Strong possibility of multipath noise and fading noise caused
by the changes of FM waves. Noise occurs when listening to faint
broadcasting.
Noise occurs only at night.
Noise occurs while driving on a partic-
ular area..
FM AM
HINT:
In the condition of noise occurrence does not meet any of the
above questionnaire, check the problems to ºReception
Problemº on the previous page.
- BODY ELECTRICALAUDIO SYSTEM
BE-125
2498 Author
: Date
:
2004 LAND CRUISER (RM1071U)
(2) Multipath
One type of interference caused by the bounce of
radio waves off of obstructions is called ºmultipathº.
Multipath occurs when a signal from the broadcast
transmitter antenna bounces off buildings and
mountains and interferes with the signal that is re-
ceived directly.
(3) Fade Out
Because FM radio waves are of higher frequencies
than AM radio waves, they bounce off buildings,
mountains, and other obstructions. For this reason,
FM signals often seem to gradually disappear or
fade away as the vehicle goes behind a building or
other obstruction. This is called ºfade outº.
4. NOISE PROBLEMS
(a) Questionnaire for nose:
It is very important for noise trouble shooting to have good
understanding of the claims from the customers. Refer to
the following questionnaire to diagnose the problem ac-
curately.

N17398
Example:
HeadCapstan
Pinch Roller BE-126
- BODY ELECTRICALAUDIO SYSTEM
2499 Author
: Date
:
2004 LAND CRUISER (RM1071U)
(b) Matters that require attention when checking:

Noise coming into the radio usually has no harm for
daily use as the noise protection is taken, and it is
very rate for an extremely loud noise to come in.
When extremely loud noise comes into the radio,
check if the grounding is normal where the antenna
is installed.

Check if all the regular noise prevention parts are
properly installed, and if there is any installation of
non-authorized parts and non-authorized wiring.

If you leave the radio under out of tune (not turning),
it is easy to diagnose the phenomenon as noise oc-
curs frequently.
(c) Antenna and noise:
Electronic signal received by the antenna will reach to the
radio transmitting through the core wire of the coaxial
cable. Any noise wave other than radio wave is mixed into
this core wire, that naturally causes noise in the radio and
poor sound quality. In order to prevent the noise from
coming into radio, the core wire inside the coaxial cable
is covered with a mesh wire called shield wire which trans-
mits the noise to the ground.
5. COMPACT DISC PLAYER
Compact Disc Players use a laser beam pick-up to read the dig-
ital signals recorded on the CD and reproduce analog signals
of the music, etc.
HINT:
Never attempt to disassemble or oil any part of the player unit.
Do not insert any object other than a disc into the magazine.
NOTICE:
CD players use an invisible laser beam which could cause
hazardous radiation exposure. Be sure to operate the play-
er correctly as instructed.
6. Tape player/head cleaning:
MAINTENANCE
(a) Raise the cassette door with your finger.
Next, 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.

BE4331
I10058
Radio Receiver Assembly Power Amplifier DVD Auto Changer
- BODY ELECTRICALAUDIO SYSTEM
BE-127
2500 Author
: Date
:
2004 LAND CRUISER (RM1071U)
7. CD player/disc cleaning:
MAINTENANCE
If the disc gets dirty, clean the disc by wiping the surface from
the center to outside in the radial directions with a soft cloth.
NOTICE:
Do not use a conventional record cleaner or anti-static pre-
servative.
8. OUTLINE OF AVC-LAN
(a) What is AVC-LAN?
AVC-LAN is the abbreviation, which stands for Audio Visual Communication-Local Area Network.
This is a unified standard co-developed by 6 audio manufactures associated with Toyota Motor Corpo-
ration.
The Unified standard covers signals, such as audio signal, visual signal, signal for switch indication
and communication signal. Radio receiver assembly and RSA (Rear Seat Audio) panel have a resis-
tance (60 - 80 W) required for communication.
(b) Objectives
Recently the car audio system has been rapidly developed and functions have been changed drasti-
cally. The conventional system has been switched to the multi-media type such as a navigation sys-
tem. At the same time the level of customers needs to audio system has been upgraded. This lies be-
hind this standardization.
The concrete objectives are explained below.
(1) When products by different manufactures were combined together, there used to be a case that
malfunction occurred such as sound did not come out. This problem has been resolved by stan-
dardization of signals.
(2) Various types of after market products have been able to add or replace freely.
(3) Because of the above (2), each manufacture has become able to concentrate on developing
products in their strongest field. This has enabled many types of products provided inexpensive-
ly.
(4) In general, a new product developed by one particular manufacture could not be used due to
a lack of compatibility with other manufactures products. Because of this new standard, users
can enjoy many compatible products from different manufacture anytime they went.
(c) The above descriptions are the objectives to introduce AVC-LAN. By this standardization, develop-
ment of new products will no longer cause systematic errors.

I25240
AVC-LAN:
Main AVC-LAN
Power Amplifier (*)
RSA Panel Radio Receiver Assembly DVD Auto Chager
*: Except JBL System BE-128
- BODY ELECTRICALAUDIO SYSTEM
2501 Author
: Date
:
2004 LAND CRUISER (RM1071U)
HINT:

When +B short or GND short is detected in AVC-LAN circuit, communication stops. And audio system
does not function normally.

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

This system has 2 kinds of AVC-LAN, Main AVC-LAN and Sub AVC-LAN.

RSA panel works as a master unit in the Sub AVC-LAN, but not in the Main AVC-LAN.

The car audio system using AVC-LAN circuit has a diagnosis function.
(w/ Navigation system (see pageDI-1263)

Each product has its own specified numbers called physical address. Numbers are also allotted to
each function in one product, which are called logical address.

I25541
1 2 3 4 5 6 7
8 9 10 11 12 13 14 15 16
BE2EA-01
I25540
- BODY ELECTRICALAUDIO SYSTEM
BE-171
2544 Author
: Date
:
2004 LAND CRUISER (RM1071U)
INSPECTION
1. INSPECT POWER AMPLIFIER CIRCUIT
Disconnect the connector from power amplifier and inspect the
connector on the wire harness side.
Tester connectionConditionSpecified condition
12 - GroundConstantContinuity
13 - GroundConstantContinuity
7 - GroundConstantBattery voltage
16 - GroundConstantBattery voltage
If the circuit is not as specified, inspect the circuits connected
to other parts.
2. INSPECT REAR SEAT AUDIO CIRCUIT
Disconnect the connector from RSA controller and inspect the
connector on the wire harness side.
Tester connectionConditionSpecified condition
17 - GroundConstantContinuity
24 - GroundIgnition switch LOCK and radio switch ONNo voltage
24 - GroundIgnition switch ACC or ON and radio switch ONBattery voltage
12 - GroundConstantBattery voltage
If the circuit is not as specified, inspect the circuits connected
to other parts.

I25542
I25539
Connector ºAº
Connector ºBº
Connector ºCº BE-172
- BODY ELECTRICALAUDIO SYSTEM
2545 Author
: Date
:
2004 LAND CRUISER (RM1071U)
3. INSPECT DVD CHANGER CIRCUIT
Disconnect the connector from DVD changer and inspect the
connector on the wire harness side.
Tester connectionConditionSpecified condition
20 - GroundConstantContinuity
1 - GroundIgnition switch LOCKNo voltage
1 - GroundIgnition switch ACC or ONBattery voltage
10 - GroundConstantBattery voltage
If the circuit is not as specified, inspect the circuits connected
to other parts.
4. INSPECT RADIO RECEIVER ASSEMBLY CIRCUIT
Disconnect the connectors from the radio receiver assembly,
and inspect the connector on the wire harness side.
Tester connectionConditionSpecified condition
A20 - GroundConstantContinuity
A1 - GroundConstantBattery voltage
A11 - GroundIgnition switch LOCKNo voltage
A11 - GroundIgnition switch ACC or ONBattery voltage
If the circuit is not as specified, inspect the circuits connected
to other parts.