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TROUBLESHOOTING
NO RASTER
CHECK +B
at D807 cathode
Normal Abnormal
Check Open
Is the voltage at pin37
FUSE of AC line
& 12 of IC501 8V?
No
OK Check /replace
Yes Check the in/out Fuse,DB801,IC803
of IC844
Check pin40 Check the voltage
No of C806
of IC501(H-out) 0V
No
Check &replace
Yes 254~380V Check /replace
IC501
Check u-COM DB801,R811
Check Q402 pin28 low?
Check the voltage
No collector waveform at pin4 of IC804
Check T401 & No
each pin voltage
Check /replace
Q807 Check /replace
D806,IC804,R809,R810
NO TELETEXT
Check
CVBS signal
at IC01 pin12
OK Check
IC01 & IICBus Line
Not OK
Check / Replace
Q10 & IC501
- 16 -
NO SOUND / PICTURE OK
Check the voltage of SMPS
25V at pin9 of IC601
Abnormal Normal(20~25V)
Check/Replace of Check the voltage
FR803 & D804 swing of pin2 of IC501
Check demodulated
signal of pin15 of IC501
Check demodulated
Check/Replace IC501 of input pin of IC601
Check/Replace IC01
Check/Replace IC601
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 IC501, pin18 T701
Not OK OK Not OK OK Not OK
Check/Replace Check
Check
CPT Board FR704, FR901
FBT T701
Components P902A & P902B
Check
Check
IC501, ZD904
FBT T701
P901A & P901B
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NO PICTURE / NO SONUD
Is any OSD displayed?
No
Yes
OK Check IC01 pin38,39,40 Check receiving system in MENU
(R,G,B) & excute Auto-program.
Not OK
Check IC01 pin19,20 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 /
( IC501 pin6 )
TUNER, IC501 PICTURE OK
OK
Check Not OK
Check R,G,B signal
CVBS singal Line at IC501 pin19,20,21
& IC501
OK
Check / Replace
CPT Board component
- 18 -