2001 TOYOTA PRIUS audio

2001 PRIUS (EWD414U)
SRS
NOTICE: When inspecting or repairing the SRS, perform the operation in accordance with the following precautionary
instructions and the procedure and precautions in the Repair Manual for the applicable model year.

Malfunction symptoms of the SRS are difficult to confirm, so the DTCs become the most important source of information
when troubleshooting. When troubleshooting the SRS, always inspect the DTCs before disconnecting the battery.

Work must be started after 90 seconds from when the ignition switch is turned to the ºLOCKº position and the
negative (±) terminal cable is disconnected from the battery.
(The SRS is equipped with a back±up power source so that if work is started within 90 seconds from
disconnecting the negative (±) terminal cable of the battery, the SRS may be deployed.)

When the negative (±) terminal cable is disconnected from the battery, the memory of the clock and audio system will be
canceled. So before starting work, make a record of the contents memorized in the audio memory system. When work is
finished, reset the audio systems as they were before and adjust the clock. To avoid erasing the memory in each
memory system, never use a back±up power supply from outside the vehicle.

Before repairs, remove the airbag sensor if shocks are likely to be applied to the sensor during repairs.

Do not expose the steering wheel pad, front passenger airbag assembly, side airbag assembly, seat belt pretensioner,
airbag sensor assembly or side airbag sensor directly to hot air or flames.

Even in cases of a minor collision where the SRS does not deploy, the steering wheel pad, front passenger airbag
assembly, side airbag assembly, seat belt pretensioner, airbag sensor assembly and side airbag sensor assembly
should be inspected.

Never use SRS parts from another vehicle. When replacing parts, replace them with new parts.

Never disassemble and repair the steering wheel pad, front passenger airbag assembly, side airbag assembly, seat belt
pretensioner, airbag sensor assembly or side airbag sensor assembly in order to reuse it.

If the steering wheel pad, front passenger airbag assembly, side airbag assembly, seat belt pretensioner, airbag sensor
assembly or side airbag sensor assembly has been dropped, or if there are cracks, dents or other defects in the case,
bracket or connector, replace them with new ones.

Use a volt/ohmmeter with high impedance (10 kW/V minimum) for troubleshooting the system's electrical circuits.

Information labels are attached to the periphery of the SRS components. Follow the instructions on the notices.

After work on the SRS is completed, perform the SRS warning light check.

If the vehicle is equipped with a mobile communication system, refer to the precaution in the IN section of the Repair
Manual.

NEW MODEL OUTLINE
MAIN EQUIPMENT
182MO20
[Information Screen]
This screen indicates the direction of energy trans-
mission. It is also possible to check the current drive
method (engine, motor or both) and status of power
generation by the engine and that of charging regen-
erative energy.
This screen indicates the average fuel consumption,
amount of recovered energy and fuel consumption for
that moment. Average fuel consumption is displayed
at 5-minutes intervals. The recovered energy display
indicates the amount of energy recovered over the past
5 minutes, with each mark representing 50Wh.
182BE36
182BE37
17
A range of features for comfort - the more you use them,
the better they get.
Multi-Information Display

The 5.8º wide touch panel type multi-information color LCD
is standard.

Energy monitor, fuel consumption and other vehicle information
screens, audio operation status and audio operation screen can
be indicated on the multi-information display. The outside tem-
perature are also indicated on the screen.
[Audio system]

An AM/FM cassette and 4-speaker system compatible with the
multi-information display has been adopted.

As the touch panel type display is used to operate the audio sys-
tem, the multi-information display simultaneously indicates the
operating status of the audio system.

The antenna provided is a collapsible style pole antenna posi-
tioned at the center of the roof.
[GPS Voice Navigation]

A GPS (Global Positioning System) voice navigation system
is optional.

The multi-information display can show the map on favorite
type among turn list, arrow display and enlarged intersection.

Using DVD (Digital Versatile Disk) as a memory source for map
data, a large quantity of information can be processed.
 Main Function of the Multi-information Display
ScreenFunction
Enlargement / reduction, rotation and move-
ment of map
Mapscreen
Indication of current position and direction of
travel
Map screen
displayCorrection of current positiondis lay(option)Setting, change and indication of route()
Voice guidance
Indication of enlarged intersections
Memory and indication of map position
Audio screenStatus of audio equipment and audio opera-
tion screen indication
InformationEnergy monitor screen indicationInformationscreenFuel consumption screen indication
Adj t tSound quality adjustment screen indicationAdjustmentscreenImage quality adjustment screen indicationscreenNo indication
On-screenAudio status indicationOn screenindicationWarning indication
Interrupt screenWarning indication
DiagnosisscreenDisplays system diagnosisscreen
displayDisplays various types of coefficient settings

THS (TOYOTA HYBRID SYSTEM)
182TH26
Inverter
Converter
182TH17
F. L
MAINF.L DCDC12 V

Output
Auxiliary
Battery S34B20
Shielded 12 VInverter
SDC273.6 V
DC / DC Converter
Input Filter
20 V
Converter Control Circuit
HV ECU A / C ECUIG
IDH NODD 36
CONVERTER
1. General
The power source for auxiliary equipment of the
vehicle such as the lights, audio system, and the air
conditioner cooling fan, as well as the ECUs, is
based on a 12 V system. Because the THS genera-
tor outputs at 273.6 V, the converter is used to
transform the voltage from DC273.6 V to DC 12
V in order to recharge the auxiliary battery. The
converter is installed on the underside of the in-
verter.
2. Operation

The DC273.6 V input is initially converted into alternating current by the transistor bridge circuit and
transformed into a low voltage by the transformer. After this, the current is rectified, smoothed (into direct
current) and converted into DC12 V.

The voltage at the positive terminal of the auxiliary battery is monitored by the converter and is maintained
at a constant level. Consequently, the voltage of the auxiliary battery is unrelated to the engine rpm (even
if the engine is stopped) and to the auxiliary equipment (output current of converter).

BODY ELECTRICAL
BODY ELECTRICAL ± BATTERY AND MULTIPLEX COMMUNICATION SYSTEM
182BE01
: BEAN : UART
: AVC-LAN : Serial Data
Link
Brake ECU
HV ECU
Air Condi-
tioning ECU
Meter ECU
ECM
Body ECU
Display ECU
Audio
ComponentsGateway
ECU
Power Window
Master SwitchDoor Con-
trol ReceiverBattery ECU
141
AUXILIARY BATTERY
DESCRIPTION
All the body electrical systems and auxiliary equipment operate using the same 12 V battery used on ordinary
gasoline engine vehicles.
However, as the battery structure is different, Prius uses an exclusive battery. See page 42 in the THS (TOYOTA
Hybrid System) section for details of the auxiliary battery structure.
MULTIPLEX COMMUNICATION SYSTEM
DESCRIPTION
A multiplex communication system has been adopted for body electrical system control and to achieve
a slimmer wiring harnesses configuration.
BEAN (Body Electronics Area Network) has been adopted between the body ECU, ECM, meter ECU,
air conditioning ECU, and the gateway ECU. Furthermore, AVC-LAN (Audio Visual Communication-
Local Area Network) has been adopted between the display ECU and the audio components.
The conversion of communication signals between BEAN and AVC-LAN is performed by the gateway
ECU.
UART (Universal Asynchronous Receiver Transmitter), which performs unidirectional communication,
has been adopted between the body ECU and the power window master switch.
A serial data link has been adopted between the body ECU and the door control receiver. In addition, a
serial data link has been adopted between the ECM, HV ECU, brake ECU, and the battery ECU, which
pertain to the control of the hybrid system.

System Diagram 

BODY ELECTRICAL ± MULTIPLEX COMMUNICATION SYSTEM 142
SYSTEM OPERATION
1. General
The ECUs that pertain to the body electrical system perform the functions and system controls described be-
low.
Gateway ECU
Conversion of data between AVC-LAN and BEAN
Transmission of vehicle information to the display ECU, in order for it to be displayed on multi-informa-
tion display
Body ECU
Power window system control (Front, Rear passenger only)
Door lock control system control
Wireless door lock remote control system control
Theft deferrent system control
Daytime running light system control
Illuminated entry system control
Light auto turn-off system control
Seat belt warning system control
Key reminder system control
Diagnosis
Meter ECU
Meter control
Illumination and flashing control of indicator and warning lights
Sounding control of warning buzzer
Air Conditioning ECU
Air Conditioning control
ECM
Engine control
Diagnosis
Display ECU
Transmission and reception associated with audio and visual functions

BODY ELECTRICAL ± MULTIPLEX COMMUNICATION SYSTEM
182BE02
Display ECU
CPU
AV C - L A N
Transmis-
sion
Reception
ControlAVC-LAN
Transmis-
sion
Reception
CircuitAVC-LANGateway ECU
CPU
AVC-LAN
Transmis-
sion
Reception
CircuitCon-
version
ControlBEAN
Trans-
mission
Recep-
tion
Circuit
Audio
Components
BEAN
Body ECU Meter ECU
143
2. Gateway Function (Gateway ECU)
This multiplex communication system has adopted BEAN (Body Electronics Area Network) between the
body ECU, ECM, meter ECU, air conditioning ECU, and the gateway ECU, as well as AVC-LAN between
the display ECU and the audio components. Because the data configuration differs between BEAN and AVC-
LAN, their data must be converted in order for them to exchange each other's data. The conversion of com-
munication data is performed by the gateway ECU. As a result, it has become possible for a single commu-
nication line to transmit various types of information.

BODY ELECTRICAL ± ACCESSORIES173
ACCESSORIES
MULTI-INFORMATION DISPLAY
1. General
A multi-information display has been provided on top of the center console as standard equipment.
Consisting of a 5.8-inch wide LCD (Liquid Crystal Display) screen, this multi-information display pro-
vides a vehicle information screen, warning screen, and an audio operation screen. The outside tempera-
ture is also shown on the screen.
A GPS (Global Positioning System) voice navigation is offered as an option. Through the use of the GPS
and the map data in a DVD (Digital Versatile Disc), this navigation system analyzes the position of the
vehicle and indicates that position on the map that is displayed on the screen. Additionally, it provides
voice instructions to guide the driver through the route to reach the destination that has been selected.
Listed below are the main functions of the multi-information display.
Function
Outline
Map Screen Display*
Enlargement / reduction, rotation and movement of map.
Indication of current position and direction of travel.
Correction of current position.
Setting, change and indication of route.
Voice guidance.
Indication of enlarged intersections.
Memory and indication of map position.
Audio Screen DisplayStatus of audio equipment and audio operation screen indication.
Information
Screen DisplayEnergy monitor screen indication.
Fuel consumption screen indication.
Adjustment
Screen DisplaySound quality adjustment screen indication.
Image quality adjustment screen indication.
No indication.
On-screen DisplayAudio status indication.
Warning indication.
Interrupt Screen
DisplayWarning indication.
Diagnosis Screen
DisplayDisplay system diagnosis.
Displays various type of coefficient settings.
*: with GPS Voice Navigation System

BODY ELECTRICAL ± ACCESSORIES
182BE34
Navigation
ECUGPS Antenna
AVC-LANBEAN
Gateway
ECUMeter
ECUECM
Center Cluster
Switches
 Navigation-related
 switches
 Audio-related
 switches
Display
ECU
Multi-information
DisplayAudio Unit Front LH
Speaker
(Voice
Guidance)
182BE35
GPS Antenna*
Navigation ECU*
DVD*
Center Cluster Switches
and Audio UnitMulti-information
Display 174
2. System Diagram
3. Layout of Components
*: with GPS Voice Navigation System