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TROUBLE SHOOTING
NO RASTER
CHECK +B
at D807 cathode
Normal Abnormal
Check Open
Is the voltage at pin61,56
FUSE of AC line
& 54 of IC01 3.3V?
Yes OK Check /replace
No Fuse,DB801
Is the voltage at pin3 Is the voltage at pin14 Check the voltage
of IC02 5V? & 39 of IC01 8V? of C806
No 0V
Yes
No Yes Check the in/out 254~380V Check /replace
Check / Replace Check the In/Out of IC844 DB801
IC01,IC02 of IC842 Check pin33
No Check the voltage
of IC01(H-out)
No No pin3 of IC803
Check &replace
Check the voltage IC01 Yes
at D805 or D815 Check IC01
cathode Check Q402 pin1 high?
No collector waveform Check /replace
No IC801,IC803,IC804
Check / Replace Check &replace
Yes
F812 Q402
Check T402
& each pin voltage
No
Check &replace Yes
T402
Check &replace
T402
NO RASTER / SOUND OK
Check the
Heater voltage of CPT
(6 ~ 6.5Vrms)
OK Not OK
Check Check Check the
HV, Screen voltage of Ik Current of Heater pulse of FBT
CPT IC01,pin50 T401
Not OK OK Not OK OK Not OK
Check/Replace
Check Check
CPT Board
FR404,FR902,P302 FBT T401
Components
Check
Check
IC01,ZD901
FBT T401
IC901,P902,P541
NO SOUND / PICTURE OK
MONO
Select correct system
in menu
OK
Check the waveform NO Check the waveform NO Check the waveform
at pin 44 of IC01 at pin 35 of IC501 at pin 4 of IC651
OK NO
Check the waveform NO Check the waveform
Check/Replace Q621
at pin 1 of IC601 at pin 2,7 of IC651
OK NO
Check the waveform NO Check the waveform
Check/Replace IC601
at pin 4 of IC601 at pin28 IC01 NO
OK
OK
Check the voltage NO Check/Replace
FR803,D804 Check / Replace Check/Replace
at pin 5 of IC601 IC01
IC651
RF STEREO
Select correct system
in menu
OK
Check the waveform NO Check / Replace
at pin 16 of TU101 TU101
OK
Check the waveform NO Check the voltage NO Check the voltage
at pin 24,25 of IC661 at pin 16,33,46 of IC661 at pin1 of IC131
OK NO
Check the waveform NO Check/Replace Check/Replace
at pin 4,12 of IC602 Q671,Q672 IC131,IC661
OK
Check the voltage NO Check/Replace
at pin 6,7 of IC602 Q621,IC603
OK
Check the waveform
at pin 1,2,14,15 of IC602
OK
Check the voltage NO Check/Replace
at pin 3,13 of IC602 F811,D824
NO PICTURE / NO SONUD
Is any OSD displayed?
No
OK
OK Check IC01 pin50,51,52,53 Check receiving system in MENU
(IK,R,G,B) & excute Auto-program.
NO
Check/ Replace Does the Auto-program OK
IC01 operate properly.
NO
Store in manual-program MENU
Check NO Check 5V, 33V & IIC Bus Line
5V, 33V & of TUNER
IIC Bus Line
OK
Go to
NO Is the CVBS signal OK.
Check / Replace NO SOUND /
( IC01 pin40 )
IC01,TUNER PICTURE OK
OK
Check OK Check IK NO Check R,G,B signal
CVBS singal Line signal at IC01 pin50 at IC501 pin51,52,53
& IC01 (similar to CVBS)
OK
Check / Replace
CPT Board component
AV STEREO
Select correct system
in menu
OK
Check the waveform NO Check / Replace
at pin 44 of IC01 IC01
OK
Check the waveform NO Check the voltage
at pin 15,18 of IC631 at pin 6 of IC631
OK
Check the waveform NO Check/Replace
at pin 4,12 of IC602 IC602
OK
Check the voltage NO Check/Replace
at pin 6,7 of IC602 Q621,IC603
OK
Check the waveform
at pin 1,2,14,15 of IC602
OK
Check the voltage NO Check/Replace
at pin 3,13 of IC602 F811,D824