2008 GEELY MK radio antenna

Wave band LF MF HF VHF
Radio wave AM FM
Modulation Amplitude modulation Frequency modulationFrequency 30KHZ 300KHZ 3MHZ 30MHZ 300MHZ
2. Area coverage
Scope of AM and FM broadcasting coverage area differs greatly.
Sometimes although AM broadcast may be received clearly, FM
binaural broadcasting cannot be received. Not only listening zone of
FM binaural broadcasting is small, but also static noise or other
cacophony (noise) tends to occur.
3. Receiving problem
Notes:
Besides static noise problem, there is also interference, multiplex
and attenuation. These problems are not caused by electric cacophony,
but the problem of radio wave itself.
(1) Interference
Besides static noise problem, AM broadcast tends to receive
other types of noise, especially at night. This is because ionosphere
reflects AM radio wave at night, these interference electric waves
interfere with signals from the same signal source while entering into
vehicle antenna directly, this kind of noise is called "interference".
(2) Multiplex
Noise caused by radio wave reflected from barrier is called
"multiplex". When radio signal emitted by broadcast antenna is
reflected by high buildings or high mountains, and disturbs directly
received other signals, multiplex phenomenon occurs.
(3) Attenuation
Since its frequency is higher than AM, FM wave is more easily
reflected by high buildings or high mountains. Therefore, FM signal
often disappears gradually, or when vehicle is blocked by barrier, it
cannot receive any signal, such phenomenon is called "attenuation".Audio System -Audio System Description5-38Chapter 5 Audio SystemSection 1 Audio System DescriptionDescription:
1. Radio wave band
Wave bands used in radiobroadcast are as follows:
LF: low frequency MF: medium frequency HF: high frequency VHF: very high frequencyFM (stereo)
FM (non-stereo)
AMInterference
IonosphereMultiplexAttenuation

Suspected Area
1. Radio assembly circuit faulty
2. Radio assembly
1. Radio assembly backlight terminal
2. Radio assembly
1. Speaker circuit
2. Radio assembly power circuit faulty
3. Radio assembly
1. Speaker circuit
2. Radio assembly power circuit faulty
3. Radio assembly
1. Antenna circuit
2. Radio assembly
1. Tape
2. Radio assembly power circuit faulty
3. Radio assembly
1. Tape
2. Radio assembly
1. Tape
2. Radio assembly
1. Tape
2. Radio assembly
1. Wire between CD box and main unit
2. CD Player main unit power supply circuit fault
3. CD box
4. CD Player main unit
1. Wire between CD box and main unit
2. CD box
3. CD bag
4. CD Player main unitSection 3 Audio System InspectionI. Symptom analysisSymptom
The system doesn't work when power is ON.
The radio backlight does not light up with the
illumination switch ON
Speaker soundless in all modes
Poor sound quality in all modes (Volume faint)
Unable to receive radio broadcast (poor
reception)
The cassette could not be inserted or played
Cassette tape will not be ejected
Poor sound quality only when playing cassette
tape
Tape jammed, malfunction with tape speed or
auto-reverse
CD could not be inserted or ejected after in-
serted
CD player doesn't work even if power is onAudio System -Audio System Inspection5-41

Tester Connection Condition Standard Status
+B - GND Normal 10~14V
ACC - GND Ignition switch ACC or ON 10~14V
Abnormal: Repair or replace wire harness and connector
Normal: Check and replace radio assembly
4. Unable to receive radio broadcast (poor reception)
(1) Check if the radio auto-research function works
Perform the radio auto-research function to see if it works
Normal: Check and replace radio assembly
Abnormal: Check the antenna for noise
(2) Check the antenna for noise
a. Turn on radio to AM with the ignition switch ACC.
b. Touch the antenna of the seated antenna assembly with the tip of the screwdriver.Check the speaker for
noise.
Standard: There is noise
Normal: Check and replace radio assembly
Abnormal: Check antenna assembly
(3) Check antenna assembly
a. Remove the antenna plug from the antenna assembly
b. Check for noise

Connect the radio assembly connector and turn the ignition switch to ACC.

Turn on the radio to AM

Insert a flat pan screwdriver or metal object similar to thin wire into the hole in the antenna coaxial
cable. Check the speaker for noise.
Standard: There is noise.
Normal: Check and replace radio assembly
Abnormal: Check and replace antenna coaxial cable sub-assembly
5. Cassette tape can not be inserted or played.
(1) Check for foreign object

Check the radio assembly and cassette recorder for foreign object or defect.
Abnormal: Clean foreign object
Normal: Check cassette tape
(2) Check cassette tape

Check if the cassette tape is used to record music or sound.
Replace the tape with another tape and re-check if it is faulty. b. Check the voltage between terminals under each operating condition as shown in the table below.
Standard:Audio System -Audio System Inspection5-45

Section 4 Audio System ReplacementI. Notice on operation Please explain to the customer that the AM/FM broadcast channel information will be cleared when removing
the battery negative terminal cable. Record the channel information before removing the negative terminal cable
if necessary. Reset after connecting the negative terminal cable.
All cassette tapes and CDs must be taken out before radio removal and installation.
If the cassette tapes and CDs can not be taken out due to radio fault. Do not take them out by force. Drive the
vehicle to Service Station.
Make sure the grounding bolts are tightened before antenna removal and installation.
There will be noise when receiving electric wave if the grounding bolts are not tightened.
Don't touch the speaker cone.II. Radio assembly1. Remove middle instrument board (see internal decorations)
2. Remove radio with bracket assembly
a. Remove four screws
b. Disconnect connector
3. Remove left bracket
a. Remove four screws
4. Remove right bracket
a. Remove four screws
5. Remove radio assemblyAudio System -Audio System Replacement5-52III. Front loudspeaker assembly
1. Remove door handhold
2. Remove front door electric piovted window switch assembly
3. Remove front door decorative internal plate assembly
4. Remove front door 5 inch loudspeaker assembly
a. Disconnect connector
b. Avert 3 rivets using a bit less than 4 mm (place bit in center
of rivet to bore out flange, be careful that newly cut rivet is
hot), take down loudspeaker assembly.
IV. Tweeter assembly
1. Remove door handhold
2. Remove front door electric piovted window switch assembly
3. Remove front door decorative internal plate assembly
4. Remove front door tweeter assembly
a. Disconnect connector
b. Remove two tapping screws and speaker assembly