2001 TOYOTA PRIUS radio antenna

2001 PRIUS (EWD414U)
B HOW TO USE THIS MANUAL
The ground points circuit diagram shows the connections from all major parts to the respective ground points. When
troubleshooting a faulty ground point, checking the system circuits which use a common ground may help you identify
the problem ground quickly. The relationship between ground points (
EA, IB and IC shown below) can also be
checked this way.

I GROUND POINT
FAN MAIN RELAY
FAN MAIN RELAY
A/C FAN RELAY NO.2
A/C FAN RELAY NO.3
RADIATOR FAN MOTOR
RETRACT CONTROL
RELAY
RETRACT MOTOR RH
RETRACT MOTOR LH
FRONT TURN SIGNAL
LIGHT RH
PARKING LIGHT RH
FRONT TURN SIGNAL
LIGHT LH
PARKING LIGHT LH
DOOR LOCK CONTROL
SW RH
DOOR KEY LOCK
SW RH
DOOR LOCK MOTOR
RH
BLOWER RESISTOR
A/C AMPLIFIER
RADIO AND PLAYER
HEATER RELAY
AUTO ANTENNA
MOTOR
BLOWER SW
PARKING BRAKE SW
COMBINATION METER
HORN SW [COMB. SW]
TURN SIGNAL FLASHER
DOOR KEY LOCK SW LH
DOOR LOCK MOTOR LH
FUEL CONTROL SW
WOOFER AMPLIFIER
COMBINATION METER
COMBINATION METER
FUEL SENDER
CIGARETTE LIGHTER
O/D MAIN SW
CLOCK
5
5
5
5
4
4
4
4
4BA15
IB18
EA2 10
3E5
3E
6 3G
13 3F
3 3D
1 3B
7
ID115
IC33
IA12
E 3
A
A AW±B
W±BW±B W±B
W±B W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B W±BW±B W±B W±B W±B
W±B W±B
W±BW±B
W±B
W±B
W±B W±B
W±B
BR
W±B
BR BRW±BW±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B W±B
W±B
W±B
W±B
W±B
BR W±B
BR BR
BR W±B W±BW±B
W±BW±BBR W±B (4A±GZE)
W±B A A A
I 6
I 6
I 2
I 2
I 2
B 5I 5
I 5
I 5
B 5
B 5
B 5
I 5
I 5
I 3I 3
E 3
E 3
E 3
E 2
E 4
E 5
E 4
E 5
E 6E 4
E 4
B 4
EAI 4
B 4
B 4
I 4I 8
IBIC
3C7
4
JUNCTION
CONNECTOR J 1
4
DOOR LOCK CONTROL
RELAY
ELECTRICAL IDLE-UP
CUT RELAY (M/T)FRONT SIDE MARKER
LIGHT RH
FRONT SIDE MARKER
LIGHT LH
BRAKE FLUID LEVEL
WARNING SW
UNLOCK WARNING
SW WIPER AND WASHER
SW [COMB. SW] LIGHT CONTROL SW
[COMB. SW] HEATER CONTROL
ASSEMBLY
HEATER SERVO
MOTOR AMPLIFIER
DIMMER SW
[COMB. SW]
CRUISE CONTROL
MIRROR SW
REAR WINDOW
DEFOGGER SW
POWER WINDOW
MASTER SW
POWER WINDOW
CONTROL RELAY
DOOR LOCK CONTROL
SW
REMOTE CONTROL
MIRROR SW
*The system shown here is an EXAMPLE ONLY. It is different to the actual circuit shown in the SYSTEM CIRCUITS SECTION.

BODY ELECTRICAL ± ACCESSORIES179
5. GPS (Global Positioning System) Voice Navigation
General
The GPS (Global Positioning System) function receives, via an GPS antenna, the signals that are trans-
mitted from the GPS satellites located in space at an approximate altitude of 20,000 km, in order to deter-
mine the vehicle's present position.
The GPS voice navigation function combines the radiowave navigation system that determines the pres-
ent position through the GPS signals, and the self-contained navigation system that detects the driven
distance and the direction of travel through the speed sensors and the gyro sensor that is contained in the
navigation ECU. The GPS voice navigation function is a high-precision navigation system that indicates
the vehicle position on the map display on the DVD and guides the route from the present position to the
destination on a map and pictogram and through voice instructions.
The multi-information display shows the data that has been calculated by the radiowave navigation sys-
tem and the self-contained navigation system.
Construction and Operation
The GPS voice navigation function consists of the following components:
GPS Antenna
Speed Sensor
GPS Receiver (contained in the navigation ECU)
Gyro Sensor (contained in the navigation ECU)
Navigation ECU
Speaker
For details on the basic operation of the GPS antenna and the navigation ECU, see page 175.
1) Speed Sensor
The navigation ECU will receive the vehicle speed signal directly from the meter ECU.
2) GPS Receiver
The GPS receiver demodulates the signals that are received by the GPS antenna from the satellites and
outputs them to the navigation ECU.

BODY ELECTRICAL ± ACCESSORIES
151LBE24
GPS Sateilites
Difference
Difference
Difference
Difference181
5) Detecting the Vehicle Position
The navigation ECU calculates the position based on the principle of a 3-point measurement.
The GPS satellites are equipped with high-precision clocks. Thus, the satellites are able to transmit con-
tinuous orbit signals and radiowave transmission time signals.
The navigation ECU also contains a clock, which can understand the radiowave time signals that are re-
ceived from the satellites.
As a result, the length of time that is taken by the radiowaves to arrive from the satellites to the antenna
can be determined. Thus, the lengths of time that elapse for the radiowaves of the 4 satellites to reach
the antenna are measured. Each of these lengths of time are multiplied by the luminous flux (the rate of
transmission of luminous energy: approximately 300,000 km per second), the results of which are the
distances from the satellites to the antenna. Because the positions of the GPS satellites are known by their
signals, the receiving point (vehicle position) can be rendered as the point in which the 4 spheres (of
which the centers are the respective satellites) converge.
However, due to the differences that exist between the clocks of the satellite and the ECU, the 4 spheres
do not converge at a single point. Therefore, the ECU uses another satellite to calculate the point at which
the 4 spheres converge at a single point and corrects its internal clock. As a result, the ECU determines
the vehicle position and adjusts its internal clock to the clocks of the satellites.

IN±28
± INTRODUCTIONFOR ALL OF VEHICLES
28 Author: Date:
2001 PRIUS (RM778U)
8. FOR VEHICLES EQUIPPED WITH A CATALYTIC CONVERTER
CAUTION:
If large amount of unburned gasoline flows into the converter, it may overheat and create a fire haz-
ard. To prevent this, observe the following precautions and explain them to your customer.
(a) Use only unleaded gasoline.
(b) Avoid prolonged idling.
Avoid running the engine at idle speed for more than 20 minutes.
(c) Avoid spark jump test.
(1) Perform spark jump test only when absolutely necessary. Perform this test as rapidly as possible.
(2) While testing, never race the engine.
(d) Avoid prolonged engine compression measurement.
Engine compression tests must be done as rapidly as possible.
(e) Do not run engine when fuel tank is nearly empty.
This may cause the engine to misfire and create an extra load on the converter.
(f) Avoid coasting with ignition turned off.
(g) Do not dispose of used catalyst along with parts contaminated with gasoline or oil.
9. IF VEHICLE IS EQUIPPED WITH MOBILE COMMUNICATION SYSTEM
For vehicles with mobile communication systems such as two±way radios and cellular telephones, observe
the following precautions.
(1) Install the antenna as far as possible away from the ECU and sensors of the vehicle's electronic
system.
(2) Install the antenna feeder at least 20 cm (7.87 in.) away from the ECU and sensors of the ve-
hicle's electronic systems. For details about ECU and sensors locations, refer to the section on
the applicable component.
(3) Avoid winding the antenna feeder together with other wiring as much as possible, and also avoid
running the antenna feeder parallel with other wire harnesses.
(4) Check that the antenna and feeder are correctly adjusted.
(5) Do not install powerful mobile communications system.
10. FOR USING OBD II SCAN TOOL OR TOYOTA HAND±HELD TESTER
CAUTION:
Observe the following items for safety reasons:

Before using the OBD II scan tool or TOYOTA hand±held tester, the OBD II scan tool's instruc-
tion book or TOYOTA hand±held tester's operator manual should be read thoroughly.

Be sure to route all cables securely when driving with the OBD II scan tool or TOYOTA hand±
held tester connected to the vehicle. (i.e. Keep cables away from feet, pedals, steering wheel
and shift lever.)

Two persons are required when test driving with the OBD II scan tool or TOYOTA hand±held
tester, one person to drive the vehicle and the other person to operate the OBD II scan tool or
TOYOTA hand±held tester.

EJECT Error 45 62
(CD player)Magazine cannot be ejected.
Scratched/
Reversed Disc 46 62
(CD player)Scratches or dirt is found on CD sur-
face or CD is set upside down.Replace radio receiver assembly.
Inspect CD.
Physical address: 178 Navigation ECU
Gyro Error Error in gyro sensor is detected.
(Abnormal value in voltage output
from sensor is detected for more
than specified time.)
Check the Gyro voltage in the
diagnosis system mode. 10 58
(Navigation ECU)
Map Disc Error Data cannot be read for a specified
time due to scratches or dirt on disc
surface or insertion of music CD.
Inspect disc and replace if neces-
sary. (Visually check disc surface
and wipe it with soft cloth.) 42 58
(Navigation ECU)
Vehicle speed
sensor Signal
ErrorInput error of vehicle speed sensor
signal is detected. (When no vehicle
speed sensor signal has been input
for a specified time.)
Check the vehicle speed signal in
the diagnosis system mode.

Inspect wire harness for vehicle
speed signal.

If wire harness is normal, replace
navigation ECU. 43 58
(Navigation ECU)
Player Error Malfunction of player continues for a
specified length of time.
Check if disc can be inserted/tak-
en out or not. If not , replace naviga-
tion ECU.

When the same code is detected
in recheck after deleting the DTC
memory. 44 58
(Navigation ECU)
GPS Receiver
ErrorOperation error of GPS receiver is
detected.
At an outdoor site with a clear
view, operate to display the GPS in-
formation screen of the diagnosis
system. If GPS time stamp is not
properly displayed after 15 min. or
more, replace navigation ECU. 11 58
(GPS receiver)
GPS Antenna
ErrorOperation condition of GPS anten-
na cable is detected. (Open circuit,
connection failure of connectors,
etc.)
Check if the GPS antenna is cor-
rectly connected or positioned or
not. After replacing the antenna, if
the error remains, replace the navi-
gation ECU. 40 58
(GPS receiver)
Power Supply
Error of GPS
AntennaAbnormal voltage of GPS antenna
cable or short circuit is detected.
Inspect GPS antenna and replace
if necessary. (When no continuity is
identified between connector's core
and sealed part, GPS antenna is
normal.)

If GPS antenna is normal, replace
navigation ECU. 41 58
(GPS receiver)
Player Temp.
Too HighReadout cannot be done because
temperature around player's pickup
(reading part) is too high.With IG switch OFF, leave vehicle in
cool shaded place for a while and
recheck. After deleting the DTC
memory, If same code detected, re-
place navigation ECU. 45 58
(Navigation ECU)
*2: Even if no failure is detected, it may be stored depending on the battery condition or voltage for starting an engine.
*3: It is stored when 180 sec. has passed after the power supply connector is pulled out after engine start.
*4: It may be stored when the engine key is turned again 1 min. after engine start.
*5: It may be stored when the engine key is turned again after engine start.
*6: When 210 sec. has passed after pulling out the power supply connector of the master component with the ignition
switch in ACC or ON, this code is stored.
± DIAGNOSTICSNAVIGATION SYSTEM
DI±817
2001 PRIUS (RM778U)

DI±850
± DIAGNOSTICSNAVIGATION SYSTEM
2001 PRIUS (RM778U)
5 Navigation check mode (vehicle signal check mode: SPD).
NG Replace or repair speed sensor wire harness.
OK
6 Recurrence Test (Confirm the phenomenon) (Correct the current position and
drive the vehicle for a while with the GPS mark displayed).
OK Normal.
NG
Replace the navigation ECU.
7 Check if the harness is caught or sharply bent or not.
NG Navigation antenna is surely connected.
OK
8 Check optional components. (Does it become if the optionals such as the theft
deterrent system is removed?)
Yes Remove or change the position of the compo-
nents.
HINT:
Some optionals receive radio signals, and if this happens, GPS
reception may be affected.
No

DI±852
± DIAGNOSTICSNAVIGATION SYSTEM
2001 PRIUS (RM778U)
18. GPS mark does not appear.
INSPECTION PROCEDURE
1 Check the mark display. (At a place with a fine view, is GPS mark displayed or
not?)
Yes Normal.
No
2 Check if the harness is caught or sharply bent or not.
NG Navigation antenna is surely connected.
OK
3 Check optional components. (Does it become normal if the optionals such as the
theft deterrent system is removed?)
Yes Remove or change the position of the compo-
nents.
HINT:
Some optionals receive radio signals, and if this happens, GPS
reception may be affected.
No
DI7PB±01

The radio wave bands used in radio broadcasting are as follows:
Frequency
Designation
Radio wave
Modulation method
LF: Low frequency MF: Medium Frequency HF: High Frequency VHF: Very High FrequencyAmplitude modulationFrequency modulation 30 kHz
300 kHz3 MHz 30 MHz 300 MHz
LF
MFHFVHF
AM FM
BE1UU±01
BE2818
FM (Stereo)
FM (Monaural)
AM
BE2819
Fading
Ionosphere
± BODY ELECTRICALAUDIO SYSTEM
BE±95
1762 Author: Date:
2001 PRIUS (RM778U)
AUDIO SYSTEM
DESCRIPTION
1. RADIO WAVE BAND
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 comes 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.

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.