Toyota Sienna Service Manual: System description
1. Radio and navigation assembly outline
- Conventionally, 2 separate devices, a "radio and
display" and a "navigation ECU" are used. This
model has adopted a new type, combining these
devices into a single unit.
2. Navigation system outline
- Vehicle position tracking methods
It is essential that the navigation system correctly
tracks the current vehicle position and displays it on
the map. There are 2 methods to track the current
vehicle position: autonomous (dead reckoning) and
GPS* (satellite) navigation. Both navigation
methods are used in conjunction with each other.
*GPS (Global Positioning System)
Operation |
Description |
Vehicle Position Calculation |
The radio and navigation assembly calculates the current vehicle
position (direction and current position) using the direction deviation
signal from the gyro sensor and the running distance signal from the
vehicle speed sensor and creates the driving route. |
Map Display Processing |
The radio and navigation assembly displays the vehicle track on the
map by processing the vehicle position data, vehicle running track,
and map data from the map disc |
Map Matching |
The map data from the map disc is compared to the vehicle position
and running track data. Then, the vehicle position is matched with the
nearest road. |
GPS Correction |
The vehicle position is matched to the position measured by GPS.
Then, the measurement position data from the GPS unit is compared
with the vehicle position and running track data. If the position is
widely different, the GPS measurement position is used. |
Distance Correction |
The running distance signal from the vehicle speed sensor includes
the error caused by tire wear and slippage between the tires and road
surface. Distance correction is performed to account for this. The
radio and navigation assembly automatically offsets the running
distance signal to make up for the difference between it and the
distance data of the map. The offset is automatically updated. |
HINT:
The combination of autonomous and GPS
navigation makes it possible to display the vehicle
position even when the vehicle is in places where
the GPS radio wave cannot receive a signal. When
only autonomous navigation is used, however, the
mapping accuracy may slightly decline.
- Autonomous navigation
This method determines the relative vehicle position
based on the running track determined by the gyro
and vehicle speed sensors located in the radio and
navigation assembly.
- Gyro sensor
Calculates the direction by detecting angular
velocity. It is located in the radio and navigation
assembly.
- Vehicle speed sensor
Used to calculate the vehicle running distance.
- GPS navigation (Satellite navigation)
This method detects the absolute vehicle position
using radio waves from a GPS satellite.
* GPS satellites were launched by the U.S.
Department of Defence for military purposes.
Number of satellites |
Measurement |
Description |
2 or less |
Measurement impossible |
Vehicle position cannot be obtained because
the number of satellites is not enough. |
3 |
2-dimensional measurement is possible |
Vehicle position is obtained based on the
current longitude and latitude. (This is less
precise than 3-dimensional measurement.) |
4 |
3-dimensional measurement is possible |
Vehicle position is obtained based on the
current longitude, latitude and altitude. |
- Map matching
The current driving route is calculated by
autonomous navigation (according to the gyro
sensor and vehicle speed sensor) and GPS
navigation. This information is then compared with
possible road shapes from the map data in the map
disc and the vehicle position is set onto the most
appropriate road.
- Touch switch
Touch switches are touch-sensitive (interactive)
switches operated by touching the screen. When a
switch is pressed, the outer glass bends in to
contact the inner glass at the pressed position. By
doing this, the voltage ratio is measured and the
pressed position is detected.
3. DVD (Digital Versatile Disc) player outline (for
navigation map)
- The radio and navigation assembly (built-in
navigation ECU) uses a laser pickup to read the
digital signals recorded on a DVD.
HINT:
- Do not disassemble any part of the radio and
navigation assembly (built-in navigation ECU).
- Do not apply oil to the radio and navigation
assembly (built-in navigation ECU).
- Do not insert anything but a DVD into the radio
and navigation assembly (built-in navigation
ECU).
CAUTION:
Do not look directly at the laser pickup because
the radio and navigation assembly (built-in
navigation ECU) uses an invisible laser beam.
Be sure to only operate the navigation system
as instructed.
4. CD (Compact Disc) player outline
- A compact disc player uses a laser pickup to read
digital signals recorded on a compact disc (CD). By
converting the digital signals to analog, it can play
music and other things.
NOTICE:
- Do not disassemble any part of the CD player.
- Do not apply oil to the CD player.
- Do not insert anything but a CD into the CD
player.
CAUTION:
Do not look directly at the laser pickup because
the CD player uses an invisible laser beam. Be
sure to only operate the player as instructed.
- Usable discs
- This player can only play audio CDs, CD-Rs
(CD-Recordable), and CD-RWs (CDReWritable)
that have any of the following
marks:
- Precautions for use of discs
NOTICE:
HINT:
- When it is cold or it is raining, if the windows mist
up, mist and also dew may form in the player. In
such a case, the CD may skip or the CD may
stop in the middle of play. Ventilate or dehumidify
the cabin for a while before using the player.
- The CD may skip if the player experiences strong
vibrations when the vehicle is driven on rough
road or similar uneven surface(s).
- Cleaning
NOTICE:
Do not use a lens cleaner because it may cause
a malfunction in the pickup portion of the player.
- If dirt is on the disc surface, wipe it clean with a
soft dry cloth such as an eyeglass cleaner for
plastic lenses from the inside to the outside in a
radial direction.
NOTICE:
- Pressing on the disc by hand or rubbing
the disc with a hard cloth may scratch the
disc surface.
- Use of solvent such as a record spray,
antistatic agent, alcohol, benzine, and
thinner, or a chemical cloth may cause
damage to the disc, making the disc
unusable.
5. MP3 / WMA OUTLINE
- Playable MP3 file standards
- Playable WMA file standards
- ID3 tag and WMA tag
- Additional textual information called ID3 tag can
be input to MP3 files. Information such as song
titles and artist names can be stored.
HINT:
This player is compatible with the ID3 tags of ID3
Ver. 1.0 and 1.1, and ID3 Ver. 2.2 and 2.3.
(Number of characters complies with ID3 Ver.
1.0 and 1.1.)
- Additional textual information called WMA tag
can be input to WMA files. Information such as
song titles and artist names can be stored.
- Usable media
- Only CD-ROMs, CD-Rs (CD-Recordable), and
CD-RWs (CD-ReWritable) only can be used to
play MP3/WMA files.
NOTICE:
- CD-Rs and CD-RWs are more easily
affected by a hot and humid environment
than discs used for normal audio CDs. For
this reason, some CD-Rs and CD-RWs
may not be played.
- If there are fingerprints or scratches on
the disc, the disc may not be played or the
CD may skip.
- Some CD-Rs and CD-RWs deteriorate if
they are left in the cabin for a long time.
- Keep CD-Rs and CD-RWs in a storage
case that is impenetrable to light.
- Usable media format
- Usable media format
HINT:
- As for MP3/WMA files written in any format
other than those above, the contents of the
files may not be played normally or the file
names or folder names may not be displayed
correctly.
- This player is compatible with multi-session
discs and can play CD-Rs and CD-RWs on
which MP3/WMA files are added. However,
only the first session can be played.
- Discs whose first session includes both music
data and MP3 or WMA format data cannot be
played.
- Standard and restrictions
- File names
- Only files with an extension of ".mp3" or ".wma"
can be recognized and played as MP3 or WMA
files.
- Save MP3 or WMA files with an extension of
".mp3" or ".wma".
NOTICE:
If saving non-MP3 or non-WMA files with an
extension of ".mp3" or ".wma", those files
are wrongly recognized as MP3 orWMA files
and played. A loud noise may occur and
damage to the speaker may result.
6. AVC-LAN Description
- What is AVC-LAN?
AVC-LAN, an abbreviation for "Audio Visual
Communication Local Area Network", is a united
standard developed by the manufacturers in
affiliation with Toyota Motor Corporation. This
standard pertains to audio and visual signals as well
as switch and communication signals.
- 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:
- To solve sound problems, etc. caused by using
components of different manufacturers through
signal standardization.
- To allow each manufacturer to concentrate on
developing products they do best. From this,
reasonably priced products can be produced.
HINT:
7. Communication system outline
- Components of the navigation system communicate
with each other via the AVC-LAN.
- The radio and navigation assembly has enough
resistance (60 to 80 Ω) necessary for
communication.
- If a short circuit or open circuit occurs in the AVCLAN
circuit, communication is interrupted and the
navigation system will stop functioning.
8. Diagnostic function outline
- The audio system has a diagnostic function (the
result is indicated on the master unit).
- A 3-digit hexadecimal component code (physical
address) is allocated to each component on the
AVC-LAN. Using this code, the component in the
diagnostic function can be displayed.
9. Bluetooth outline
- Bluethooth is a trademark owned by Bluetooth SIG.
Inc.
- Bluetooth is a new wireless connection technology
that uses the 2.4 GHz frequency band. This makes
it possible to connect a cellular phone (Bluetooth
compatible phone *1) to the radio and navigation
assembly (the Bluetooth system is built in), and use
the handsfree function of the cellular phone, even if
it is in a pocket or bag. As a result, it is not
necessary to use a connector attached directly to
the cellular phone.
*1: Some versions of Bluetooth compatible cellular
phones may not function.
HINT:
The communication performance of Bluetooth may
vary depending on obstructions or radio wave
conditions between communication devices,
electromagnetic radiation, communication device
sensitivity, or antenna capacity.
PARTS LOCATION
SYSTEM DIAGRAM
...
1 VEHICLE BROUGHT INTO A WORKSHOP
2 DIAGNOSTIC QUESTIONING AND SYMPTOM CONFIRMATION
Ask the customer about symptoms and confirm
malfunctions.
3 CONFIRM THE SYSTEM NORMAL CONDITION
4 CHECK D ...
Other materials:
Inspection
1. INSPECT THERMOSTAT
(a) Inspect the thermostat.
HINT:
The valve opening temperature is inscribed on the
thermostat.
(b) Immerse the thermostat in water and gradually heat
the water.
(c) Check the valve opening temperature.
Valve opening temperature:
80 to 84°C (176 to 183°F) ...
A/F Sensor Circuit Slow Response
DTC P2A00 A/F Sensor Circuit Slow Response (Bank 1
Sensor 1)
DTC P2A03 A/F Sensor Circuit Slow Response (Bank 2
Sensor 1)
HINT:
DTC P2A00 indicates malfunctions related to the bank 1 A/F sensor.
DTC P2A03 indicates malfunctions related to the bank 2 A/F sensor.
Bank 1 r ...
Open in Front Passenger Side Squib 2nd Step
Circuit
DTC B1186/58 Open in Front Passenger Side Squib 2nd Step
Circuit
DESCRIPTION
The front passenger side squib 2nd step circuit consists of the center airbag
sensor assembly and the
front passenger airbag assembly.
The circuit instructs the SRS to deploy when deployment conditions are met.
...