Geely CK (2008). Manual part — 56
Geely CK (2008). Manual part - 56
221
Chapter 6 Audio System
Section 1 Audio System Description
Description:
1. Radio Wave Band
The radio wave bands used in radio broadcasting are as following:
LF: Low frequency
MF: Medium frequency
HF: High frequency
VHF: Very High frequency
2. Cover Area
There are great differences in the size of the
cover area for AM and FM monaural. Some-
times FM stereo broadcasts cannot be received
even though AM comes in very clearly. Not only
does FM stereo have the smallest cover area,
but it also picks up static and other types of in-
terference ("noise") easily.
3. Reception problems
Hint:
Besides the static noise fault, there are also the faults called "interference", "multipath transfer" and "fade
out". These faults are caused not by electrical noise but by the nature of the radio waves themselves.
(1) Interference
Besides static noise fault, AM broadcasts are
also susceptible to other types of noises, es-
pecially at night. This is because AM radio
waves are reflected by 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 noise is called "interference".
Band
LF
MF
HF
VHF
Radio wave
AM
FM
Modulation
Frequency 30KHZ 300KHZ 3MHZ 30MHZ 300MHZ
Amplitude modulation
Frequency modulation
FM (Stereo)
FM (Monaural)
Interference
Ionosphere
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(2) Multipath transfer
Noise caused by bouncing of radio waves off
obstructions is called "multipath transfer".
Multipath transfer occurs when a signal from
the broadcast transmitter antenna reflects off
buildings and mountains and interferes with
the signal that is received directly.
(3) Fade out
Because FM radio waves are of higher frequen-
cies than AM radio waves, they are reflected
off buildings, mountains, and other obstructions.
For this reason, FM signals often seem to gradu-
ally disappear or fade away as the vehicle goes
behind a building or other obstructions. This is
called "fade out".
4. Noise faults
For noise troubleshooting it is very important to understand the feedback information from the customers
well, so make the best use of the following questionnaire and diagnose the fault accurately.
HINT:
In the case that the noise occurrence condition does not meet any of the above, check based on the "Recep-
Multipath
Transfer
Fade out
Radio Wave
Operating condition when
noise occurs
Cause
Noise occurs at a specific
place.
Strong possibility of foreign noise.
Noise occurs when listening
to faint broadcasting.
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.
Noise occurs only at night.
Strong possibility of the interference from far distant
broadcasting.
Noise occurs while driving
and at a specific place.
Strong possibility of multipath transfer interference and
caused by the changes of FM waves.
AM
FM
223
tion Problems".
5. COMPACT DISC PLAYER
Compact Disc Players (hereinafter referred as CD) use a laser beam pick--up to read the digital signals
recorded on the CD and reproduce analog signals of the music, etc.
HINT:
Never attempt to disassemble or oil any part of the player unit.
Do not insert any object other than a disc into the disc box.
NOTICE:
CD players use an invisible laser beam which could cause hazardous radiation exposure. Be sure
to operate the player correctly as instructed.
6. MAINTENANCE
(1) Tape player/magnet head cleaning:
1
Raise the cassette door with your finger.
Next, using a pencil or similar object, push in
the guide.
2
Using a cleaning pen or cotton applicator soaked
in cleaner, clean the magnet head surface, pinch
rollers and tape press wheel.
(2) CD player/disc cleaning:
If the disc gets dirty, clean the disc by wiping the surface
from the center to outside in the radial directions with a
soft cloth.
NOTICE:
Do not use a conventional record cleaner or anti--
static preservative.
Example
Magnet Head Tape Press Wheel
Pinch Roller
224
Section 2 Audio System Connector Terminal Layout
1. Connector terminal layout on wire harness
2. Connect terminal definition
Terminal
No.
Function
Wire color
Condition
Standard Voltage
A1
FR+
Lg
The audio system is on
Wave form is synchronized with
the output sound
A2
FL+
YB
The audio system is on
Wave form is synchronized with
the output sound
A3
ACC
RW
Ignition switch turned to ACC 10~14V
A4
B+
R
Constant Status
10~14V
A5
FR-
LgR
The audio system is on
Wave form is synchronized with
the output sound
A6
FL-
Y
The audio system is on
Wave form is synchronized with
the output sound
A7
GND
B
Constant Status
Continuity
A8
Null
A9
Null
A10
TAIL
GW
Position lamp switch turned to
ON
10~14V
B1
RR+
PB
The audio system is on
Wave form is synchronized with
the output sound
B2
RL+
YR
The audio system is on
Wave form is synchronized with
the output sound
B3
RR-
P
The audio system is on
Wave form is synchronized with
the output sound
B4
Null
B5
Null
B6
RL-
YW
The audio system is on
Wave form is synchronized with
the output sound
C1
B+
Constant Status
10~14V
C2
BUS
Audio system is On
Pulse Signal
C3
GND
Constant Status
Continuity
C4
ACC
Ignition switch ACC
10~14V
C5
Null
C6
R-OUT
The audio system is on
Wave form is synchronized with
the output sound
C7
L-OUT
The audio system is on
Wave form is synchronized with
the output sound
C8
GND(Audio
Frequency)
Constant Status
Continuity
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