Downloaded from www.Manualslib.com manuals search engine 54-166CHASSlS ELECTRICAL - Radio and Tape Player
IA-7Some noise appears when there is vibration or shocks during traveling.
‘d ~
Are connectors properly connected?
YesNo
---+ Ensure proper connection
t
Does noise appear when the radio switch is turned on while theNovehicle is stopped and the radio is struck while tuned away fromLa station?
YesStatic electricity noise:
Body static electric from the shock absorber rubber bushings used
to prevent vibration, tires, etc. occurs because of separation fromthe ground, causing a buzzing noise.
Since no measures can be taken on the radio side, steps shouldbe taken to discharge the static electricitv of the vehicle bodv.
tIs the radio correctly grounded?
(Is the mounting screw tightened securely?)
1 Yes
tIs the antenna correctly grounded? (If noise appears when the Nocantenna is moved, this means the ground is not securely con-
nected.)
If rust is present on the antenna ground screw, clean and tightenthe ground securely.
Yes
1 Reoair or reolace radio.1
TSB Revision
Downloaded from www.Manualslib.com manuals search engine CHASSIS ELECTRICAL - Radio and Tape Player54-167
A-8Noise sometimes appears on FM during traveling.
NoIs the antenna completely extended?
Yes
t Check the antenna itself.
(Refer to E-l, 2.)
+Does the problem clear up whenre
1 No
Yes
iDoes the problem appear only in certain locations and only with yes
certain stations?
No
~ Due to electrical field conditions. (Multipath
noise*, fading noise*).
Are connectors property connected?
Yes
Check connector connections.1
tDoes noise appear when the radio switch is turned on while the
vehicle is stopped
and the radio is struck while tuned away froma station?
Yes
No*Static electricity noise:Sody static electric from the shock absorberrubber bushings used to prevent vibration, tires,etc. occurs because of separation from the
ground, causing a buzzing noise.
Since no measures can be taken on the radioside, steps should be taken to discharge the
static
electricitv of the vehicle bodv.
Is the radio body correctly grounded?
No(Is the mounting screw tightened securely?
)
Yes
-) Tighten the screw securely.I
Is the antenna correctly grounded? (If noise appears when the antennais moved, this means the ground is not securely connected.)
Yes
If rust is present on the antenna ground screw,clean and tighten the ground securely.
*
1 Repair or replace radio.1
About multipath noise and fading noise
Because the frequency of FM waves is extreme-
ly high, it is highly susceptible to effects from
geological formations and buildings. These ef-
fects disrupt the broadcast signal and obstruct
‘reception in several ways.l Multipath noise
This describes the echo that occurs when the
broadcast signal is reflected by a large obstruc-
tion and enters the receiver with a slight time
delay relative to the direct signal (repetitious
buzzing).l Fading noise
This is a buzzing noise that occurs when the
broadcast beam is disrupted by obstructing ob-
jects and the signal strength fluctuates intricately
within a narrow range.
1 TSB Revision
