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TROUBLESHOOTING
NO RASTER
CHECK +B at D807 cathode Normal Abnormal
Is the voltage at pin37 & 12 of IC501 8V? Yes No Check &replace IC501 No Check T401 & each pin voltage Check pin40 of IC501(H-out) Yes Check Q402 collector waveform
Check FUSE of AC line No Check the in/out of IC844 No 254~380V Check u-COM pin28 low? No Check /replace Q807 Check the voltage at pin4 of IC804 OK Check the voltage of C806
Open
Check /replace Fuse,DB801,IC803
0V Check /replace DB801,R811
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
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NO SOUND / PICTURE OK
Check the voltage of SMPS 25V at pin9 of IC601 Abnormal Normal(20~25V)
Check/Replace of FR803 & D804
Check the voltage swing of pin2 of IC501
Check demodulated signal of pin15 of IC501
Check/Replace IC501
Check demodulated 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 HV, Screen voltage of CPT Not OK OK
Check Ik Current of IC501, pin18 Not OK OK
Check the Heater pulse of FBT T701 Not OK
Check/Replace CPT Board Components
Check FR704, FR901 P902A & P902B
Check FBT T701
Check FBT T701
Check IC501, ZD904 P901A & P901B
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NO PICTURE / NO SONUD
Is any OSD displayed? No Yes OK Check IC01 pin38,39,40 (R,G,B) Not OK Check IC01 pin19,20 (V-Sync, H-Sync) Check IC01 pin36,37 (XLC, EXLC) & IC01 Check 5V, 33V & IIC Bus Line Not OK Does the Auto-program operate properly. Not OK Store in manual-program MENU Check 5V, 33V & IIC Bus Line of TUNER OK Check / Replace TUNER, IC501 Not OK Is the CVBS signal OK. ( IC501 pin6 ) OK Check CVBS singal Line & IC501 Not OK Check R,G,B signal at IC501 pin19,20,21 OK Check / Replace CPT Board component Go to NO SOUND / PICTURE OK Yes Check receiving system in MENU & excute Auto-program.
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