1999 TOYOTA CAMRY radio antenna

BE2820
Multipath
BE2821
Fade Out
AM
FMNoise occurs at a specific place.
Strong possibility of foreign noise.
Noise occurs when listening to
faint broadcasting.
Noise occurs only at night.
Noise occurs while driving and
at a specific place.There is a case that the same program is broadcasted
from each local station and that may be the case you are
listening to different station if the program is the same.
Strong possibility of the beat from a distant broadcasting.
Strong possibility of multipath noise and fading noise
caused by the changes of FM waves.
± BODY ELECTRICALAUDIO SYSTEM
BE±87
2307 Author: Date:

Multipath
One type of interference caused by bouncing of ra-
dio waves off obstructions is called ºmultipathº. Mul-
tipath occurs when a signal from the broadcast
transmitter antenna bounces off buildings and
mountains and interferes with the signal that is re-
ceived directly.

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 obstructions. This is called ºfade outº.
4. NOISE PROBLEMS
(a) Questionnaire for noise:
It is very important for noise troubleshooting to have good un-
derstanding of the claims from the customers, so that make the
best use of following quenstionnaire and diagnose the problem
accurately.
HINT:
In the case that the noise occurrence condition does not meet
any of the above quenstionnaire, check based on the ºTrouble
Phenomenonº.
Refer to previous page for multipath and fading.

N21545
NoiseGlass Printed Antenna
Signal
Radio
Noise
Noise
Noise
Noise
N21546
to Radio
Battery
Choke Coil
Noise
BE±88
± BODY ELECTRICALAUDIO SYSTEM
2308 Author: Date:
(b) Matlers that require attention when checking:

Noise coming into the radio usually has no harm for
practical use as the noise protection is taken and it
is hardly thinkable 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 out of tune (not tuning), it is
easy to diagnose the phenomenon as noise occurs
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 these noises from
mixing into the radio, the core wire inside the coaxial cable
is covered with a mesh wire called shield wire. This shield
wire shelters the noise and transmits it to the ground, thus
preventing noise from mixing in. If this shield wire has
grounding failure, that causes noise.
(d) Choke coil and noise:
The choke coil is connected in the rear window defogger
circuit. This is conneted so to prevent noise from mixing
into the radio by making the noise current included in the
power source of the rear window defogger flow to the
ground.

I03352
5
RadioEITHER AM OR FM DOES NOT WORK, RECEPTION
POOR (VOLUME FAINT), FEWER STATION PRESETS
V08242

Radio±Tape Player Unit (Built±in Power Amplifier)
Problem with radio wave signals or location?
Are both AM or FM defective?
Is power for the antenna being output from the radio assembly?
Go to No.15
Does tape player operate normally?
Temporarily install another speaker. Functions OK?
Radio assembly faulty.Poor signals, poor location.
Radio assembly faulty.
Radio assembly faulty.
Speaker faulty.

Radio±Tape Player Unit (Separate Power Amplifier)

Radio±Tape Player±CD Player Unit (Separate Power Amplifier)
Problem with radio wave signals or location?
Are both AM and FM defective?
Is power for the antenna being output from the radio assembly?
Go to No.15
Temporarily install another speaker. Functions OK?
Hiss noise from speaker?Poor signals, poor location.
Radio assembly faulty.
Radio assembly faulty.
Speaker faulty.
Power amplifier faulty.
Recheck system after repair.
Radio assembly faulty. Recheck system after repair.Ye s NoYe s Ye s Ye s Ye sYe s Ye s Ye s Ye s Ye sYe s
No
No No No No No NoNo No No
Does tape player operate normally?
Radio±CD Player Unit (Built±in Power Amplifier)

Radio±CD Player Unit (Separate Power Amplifier)
± BODY ELECTRICALAUDIO SYSTEM
BE±97
2317 Author: Date:

I01472
Is the condition bad in comparison with other vehicle?
6 Radio POOR RECEPTION
An electric wave environment.
Is there any additional installation parts? (Sun shade film,
telephone antenna etc.).Does the condition get better if removing them? Ye s
No
Ye s
No
Check if there is any scratch and breaking in a
wire on the glass antenna and the defogger pattern.
(See page
BE±115)Influence of additional installation parts. No
Repair Ye s
No
No
Is the contact of the plug jack of the radio OK?
Check for contact.
Ye s
No
Does the condition get better by using the outer
antenna? (Such as pillar antenna)Check the radio.
Ye s
No
Ye s
No Is the contact of the antenna terminal on the glass
surface and the defogger terminal?Measure for contact.
Is the continuity of the antenna cord OK? Exchange the antenna cord.
Check the grounding of the antenna, antenna cord,
choke coil and noise filter.Ye s
NG
Grounding failure.
OK
Does the condition get better by exchanging the choke
coil?Exchange the choke coil. Ye s
No
Ye s
Does the condition get better by exchanging the
antenna cord?Exchange the antenna cord.
Exchange the glass.NoYe s
BE±98
± BODY ELECTRICALAUDIO SYSTEM
2318 Author: Date:

I01473
23 Noise NOISE OCCURS
Does the noise occur only in the radio? It occurs in the cassette CD. (Go to step 13 or 20)
Does the noise occur in a particular place? An electric environment.No
Ye s
Ye s
Is there any additional installation part around the glass
printed antenna? (Sunshade film, telephone antenna, etc.)Does the noise stop by removing it?
Influence of the film of the noise radiation of
additional installation part.
Does the noise occur even pulling out the antenna cord
from the radio?
Check the radio. No
No
NoNo Ye s
Ye s
Ye s
Does the noise occur even pulling out the antenna
terminal on the glass surface?Mixing into the antenna cable.
Is there any adhesive stuck on the bases of the
antenna terminal, defogger terminal and bus bar?Failure of glass installation. Must plane the butyl rubber.
Does the noise occur even pulling out the defogger
terminal?Interfering noise from the defogger line and choke
coil. Does the condition get better by exchanging the
choke coil? Ye s
Ye s
Ye s No
No
No
Check the grounding of the antenna, antenna cord,
choke coil and noise filter.Exchange the choke coil.
NG
Grounding failure.
Does the condition get better by exchanging the antenna
cord?
Radiates directly to the antenna from the generation
source.Exchange the antenna cord.
NoYe s OK
± BODY ELECTRICALAUDIO SYSTEM
BE±111
2331 Author: Date:

BE0AZ±05
Z19489
Tweeter SpeakerTweeter Speaker
AMP
Instrument Panel J/B No.1

RADIO Fuse

DOME Fuse
Front SpeakerGlass Printed
Antenna (MAIN)
Diversity Only
(SUB)
Rear Speaker BE±114
± BODY ELECTRICALAUDIO SYSTEM
2334 Author: Date:
LOCATION

N20994
N20995
N20996
N20997
BO±78
± BODYINSTRUMENT PANEL
2426 Author: Date:
(f) Remove the bolt, nut, screw and the instrument panel as-
sembly.
23. REMOVE INSTRUMENT PANEL BRACES
(a) Remove the wire brackets and connector.
(b) Remove the bolt and connector from the No.1 instrument
panel brace.
(c) w/ Wireless Control:
Remove the nut and the wireless control unit from the
No.1 instrument panel brace.
(d) Remove the nut holding the radio antenna to the No.2
instrument panel brace.
(e) Remove a nut and brace mount bracket.
(f) Remove the 6 nuts, 2 bolts and No.1 and No.2 instrument
panel braces.
24. REMOVE INSTRUMENT PANEL REINFORCEMENT
(a) Remove the connectors from the steering column tube.
(b) Remove the 4 wire brackets and connectors.
(c) Remove the 2 nuts and bolt holding the No.1 Junction Box
(J/B) to the reinforcement.
(d) Remove the 4 nuts and the steering column from the rein-
forcement.
(e) Remove the brake pedal spring from the reinforcement
and brake pedal.
(f) Remove the 4 nuts, 3 bolts and the reinforcement.

± INTRODUCTIONFOR ALL OF VEHICLES
IN±17
17 Author: Date:
2. 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.
3. 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.