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Troubleshooting Guide

NO RASTER
CHECK +B
at D807 cathode
Normal Abnormal

Check Open
Is the voltage at pin37
& 12 of IC512 8V? FUSE of AC line
No
Check /replace
OK Fuse,D801,IC801
Yes Check the in/out
of IC841,IC842 D810,D811,D812
Check the voltage
Check pin40
No of C806
of IC512(H-out) 0V
No
Check &replace Check /replace
254~380V
IC512 Yes Fuse,D801,IC801
Check u-COM
Check Q402 pin20 low? D810,D811,D812
Check the voltage
No collector waveform
of pin4, IC803.
Check &replace No
Yes
IC512
Check /replace
Check T451 Q802
& each pin voltage Check /replace
No D806,IC803
R807,R815
Check &replace Yes
IC512
Is the voltage at pin37
& 12 of IC512 8V?
NO SOUND / PICTURE OK

AV STEREO MODEL NICAM STEREO MODEL

Select correct Select correct
system in MENU system in MENU

OK OK
NOT OK NOT OK
Check the waveform Check the waveform
of PIN4, HIC3 of PIN 7,8 P611A

OK Check / replace OK Check Vcc / replace
HIC3 NICAM BOARD
Check demodulated Check demodulated
signal of pin15, IC512 of input pin of IC601
NOT OK
OK OK
Check / replace
IC512
Check demodulated Check the Vcc
of input pin of IC601 of IC601

OK NOT OK
Check the waveform
ChecK / replace
of PIN 7,8 & Vcc
Check the Vcc IC601
AV BOARD
of IC601
NOT OK
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 IC512, pin18 T406

Not OK OK Not OK OK Not OK

Check/Replace Check
Check
CPT Board FR901
FBT T406
Components P902A & P902B

Check
Check
IC512, ZD904
FBT T406
P901A & P901B
NO PICTURE / NO SONUD
Is any OSD displayed?

No
Yes
OK Check IC01 pin30,31,32 Check receiving system in MENU
(R,G,B) & excute Auto-program.
Not OK
Check IC01 pin9,10 Does the Auto-program Yes
(V-Sync, H-Sync) operate properly.
Check IC01 pin36,37
(XLC, EXLC) Not OK
& IC01
Store in manual-program MENU

Check Not OK Check 5V, 33V & IIC Bus Line
5V, 33V & of TUNER
IIC Bus Line
OK
Go to
Not OK Is the CVBS signal OK.
Check / Replace NO SOUND /
( IC512 pin6 )
TUNER, IC512 PICTURE OK
OK
Check Not OK
Check R,G,B signal
CVBS singal Line at IC512 pin19,20,21
& IC512
OK
Check / Replace
CPT Board component
NO TELETEXT

Check the
voltage of IC701 pin19

OK 0V

Check Check 5V Supply
CVBS signal Line of IC701
at IC701 pin9 & P701

OK

OK Check
IC701& IICBus Line

Not OK

Check / Replace
Q701, X701, & IC501