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1) Front LED is Green 
2) The Set display a screen, but a sound doesnt output

1) Speaker part

Are Speaker Cables
Good?

Are Speaker Cables
connect normally?

No

Yes

No

Yes

Are Speaker units
good?

No

Exchange the cable

Insert the cable
exactly

Exchange the
Speaker unit

Is sound at HDMI

Good?

Is EDID download
good?

No

Yes

Is IC401 good?
(AD9381)

No

No

Download EDID
data once more.

Exchange IC401

Is sound at

Scart1/2 (or
Component2)RGB,
or Side AV Good?

Are good some
elements (C, R, L,
or Diode) at Sound
path? 

No

No

Yes

Yes

Is IC800 good?
(Switching IC)

No

If it dead or short,
exchange this
elements

Is sound at RF, AV,

or Component1
Good?

Are good some
elements (C, R, L,
or Diode) at Sound
path? 

No

Yes

No

If it dead or short,
exchange this
elements

Exchange IC800

Is IC601 good?
(VCT-P)

No

Exchange IC601

Yes Is IC801 good?

(Amplifier)

No

Exchange IC801

2) Main board part

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- 23 -

Video signal is received from  TUNER, AV port(AV1,AV2,S-Video) and goes to the one-chip video decoder
(VCTI) which separate the R,G,B signal and passes on the signal to AD converter(AD9883) through the video
switch(SM5301). Component signal(YPbPr) from side-jack is also passed to video switch(SM5301) and Micom
will select the desired signal(RGB from VCTi or Component from side jack).
The AD9883 converts 4:4:4 video format into digital and gives output to the Picture Enhancer (FLI2300).This
picture enhancer improves the quality of the picture by changing the level of RGB/YPbPr signals.The output of
this enhancer chip is fed to the deinterlacer ,which in turn  goes to the Scalar (GM5221).The  scalar  gives the
output on the LVDS cable which is connected to LCD module.
VCTi acts a micom and is responsible for video processing and audio signal processing.It accepts the RF
precessed signal(IF signal) from tuner/SAW-Filter and separates sound and picture from it.
Scaler is reponsible for regulating the timing of signal to LCD panel and size and location of the signal. Graphic
control accepts the PC(Analog RGB) and DVI-D (Digital) signal. The signal of PC input is connected to analog
port in Scaler and the signal of DVI-D input is connected to digital port. Thus it receives two input and switch
between them to give output at the LVDS which in turn gives output at the LCD module. 

The power board supplies a DC voltage of 33V(main power), 24V(Stand_by power), 12V(Stand_by power) to
the main board. Main power is only available after power-on and Stand_by is always available. 33V is used by
the tuner and 24V is used directly by the inverter and the sound amplifier IC. 24V also is converted into 5V-Main
Power and 5V-Stand_by by a DC/DC Converter(MP1593). The 5V is changed into 3.3V and 1.8V by a regulator.
Both voltages(3.3V, 1.8V ) is used by VCTI, Scaler, FLI2300 and AD9883. The voltage of LCD Panel is 12V

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