17
Ignition
The most common source of noise in reception is the ignition
system. This is a result of the radio being placed close to the
ignition system (engine). This type of noise can be easily
detected because it will vary in intensity of pitch with the
speed of the engine.
Usually, the ignition noise can be suppressed considerably
by using a radio suppression type high voltage ignition wire
and suppressor resistor in the ignition system. (Most vehicles
employ this wire and resistor but it may be necessary to check
them for correct operation.) Another method of suppression
is the use of additional noise suppressors. These can be
obtained from most CB radio or electronic supply shops.
Interference
Radio reception in a moving environment is very different
from reception in a stationary environment (home). It is very
important to understand the difference.
AM reception will deteriorate when passing under a bridge
or when passing under high voltage lines. Although AM
is subject to environmental noise, it has the ability to be
received at great distance. This is because broadcasting
signals follow the curvature of the earth and are reflected
back by the upper atmosphere.
Symptom
Cause
Solution
No power
The vehicle’s
accessory switch
is not on
If the power supply is
properly connected to
the vehicle’s accessory
terminal, switch the
ignition key to “ACC.”
Fuse is blown
Replace the fuse.
No sound
Volume too low
Adjust volume to
audible level.
Wiring is
not properly
connected
Check wiring
connections.
The
operation
keys do not
work
Built-in
microcomputer
is not operating
properly due to
noise
Press the
RESET
button.
Cannot tune
to radio
station,
auto-seek
does not
work
Antenna cable is
not connected
Insert the antenna
cable firmly.
Signals are too
weak.
Select a station
manually.
ERROR-01
on LCD
Database or
decoder error
Change to another
mode.
TROUBLESHOOTING