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