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NO PICTURE/
NO COLOR
Is the CVBS signal at
pin 4 of P101A normal? No
Check IF Board
Yes
Is the CVBS signal at
Pin 40 of IC201 normal? No
Check/Replace
Yes IC201
Is the Y signal at Pin 8
of IC203 normal? No
Check/Replace
Yes IC203, R223
Is the Y signal at Pin 31
of IC501 normal? No
Check/Replace
Yes IC505
Are B-Y, R-Y signal at Pins
33, 34 of IC501 normal? No
Check/Replace
Yes IC501
Are B,G,R signal at Pins 12,
13,14 of IC501 normal? No
Check/Replace
Yes IC501
Check CPT Board
NO PIP
In case of PIP (AV) In case of PIP (RF)
Is there video signal at Is there CVBS signal at
No pin 29 of IC201? pin 24 of ICP3?
No
Check/Replace
IC201 Yes Yes
Check I2C Bus Check
TUNER/IF parts
Is there video signal at of PIP
pin 26 of ICP3
No
Yes
Check PP2, PP2A
Abnormal Check pins 1, 2, 3
of ICP3
Check/Replace
ICP3, ICP2 Normal
Check pins 8,9,10,14 Abnormal
of ICP6
Check/Replace
Normal IC4P, IC5P
Abnormal Check pins 1, 4, 6, 8
of IC504
Check PP3A, PP3 Normal
Check/Replace
IC504
NO TELETEXT
Check the voltage
of C703(+)
12V
Abnormal Normal
Check the 12V line Abnormal
Check the voltage of C702(+)
to be correct
Check/Replace
IC703, D701 4.8~ 5.2V
No Check if the video signal
inputs at pin 8 of IC701 .
No Check if the video
signal inputs at the Yes
pin 40 of IC201.
Check/Replace Check I2C Bus lines
IC201 Yes (SDA, SCL)
Check the CVBS line
OK
Abnormal Check pins 15,16,17,19
of IC701
Check/Replace
IC701 Normal
Check/Replace
IC504
NO PICTURE/NO SOUND
(RASTER OK)
Does the Auto search
operate normal?
Yes No
No Is the CVBS signal at Check the voltage NG
Pin 4 of P101A normal? of Tuner (33V, 5V)
Check IF Board Check/Replace
OK ZD101, ZD102, R106
Yes
GO TO OK Check pins 20,21,
NO PICTURE Block 22,39 of IC1
NO SOUND Block
NO RASTER
(SOUND OK)
Check the voltage of
CPT Heater
Normal Abnormal
Check the voltage of Check the Heater
CPT,HV, SCREEN pulse at pin 9 of T402
Abnormal Abnormal
Check/Replace Check/Replace
T402 Normal Normal T402
Check/Replace
Check/Replace
CPT Board
Connector, R443
NO SOUND
(PICTURE OK)
Check Sound system of
station MENU OSD
(Manual Programme)
BG/I/DK M
Is the voltage at pin 25 Is the voltage at Pin 25
of IC1 0V(Low)? of IC1 5V(High)?
Yes Yes
Is the SIF signal at Pin 24
of ICI1 normal?
No
Check/Replace
Yes ICI1
Are the Audio signal at
Pin 28, 29 of ICS1 normal?
No
Check/Replace
Yes ICI2, ICS6, ICS1
Are the Audio signal at
Pins 2, 5 of IC601 normal?
No
Check/Replace
Yes ICS60
Are the Audio signal at
Pins 7, 11 of IC601 normal?
No
Check the voltage
Yes at Pin 10 of IC601
Check/Replace
P601, P602, Speaker
NO RASTER
Check +B voltage
at J401
Normal 0V
Is the voltage at Open
Check F801A
Pin 3 of IC501 9V? No
Check 5V, Check/Replace
Yes OK
9V, 12V lines F801A, D801, IC801
Does the square
waveform from pin 4 Check the voltage 0V
of IC501 appear? of C808(+)
No Yes
2
Check/Replace Check I C Bus Check/Replace
IC501 Yes lines (SDA, D801
SCL) 150~ 380V
Is the waveform at Check the voltage Lower than 6V
collector of Q401 normal? at pin 9 of IC801
No
Check/Replace Check/Replace
Q401, T401, Yes D802, D806,
R416, R417 6~ 8V D807, Q800,
IC801
Is the waveform of
collector of Q402 normal?
No Check/Replace
IC802, D803, D808
Check/Replace Check the secondary
Q402 Yes voltage are shorted
Check/Replace
T402