SHARP LC-20VM2E
Manual de Servicio

LC-121M2E LC-150M2E

LC-20VM2E

8. TROUBLE SHOOTING
No picture, No sound Fluorecent lamp failure to light up.

Do F702 and F703 function? YES Are T701's secondary outputs, +30V, +9V, +5.0V and -8V normal? NO Is T701's primary oscillator waveform normal? YES Check T701's secondary load.

NO

Does F7751 function? YES Remove F702 and F703, and check the load side. Is there short-circuiting? YES NO Is the pin 11 of IC1201 in the "H" state? YES Is primary oscillator waveform of T7751~T7756 normal ? YES Replace the fluorecent lamp with new one and check again. Replace F701 and F703.

NO

Replace F7751.

NO

Check IC1201, IC1206, IC2001 and their peripheral parts.

NO

NO

Is there short-circuiting of T701 primary side periphery, Q704 and S4701? YES

Check Q7751~Q7755, T7751~Q7756 and their peripheral parts.

Check IC702, Q702, L701 and their peripheral parts.

No picture

No picture (AV1, AV2 and Component) Is output voltages NO at pins 3,5 and 6 of IC406 normal? YES Is input voltages at NO pins 51,52 and 53 of IC801 normal? YES Is output voltages at NO pins 41,42 and 43 of IC801 normal? YES Is output voltages at pins 1 of IC315 and 1, 7 of IC316 normal? YES Is in/output voltages of IC1001 normal? YES Is in/output voltages of IC1201 normal? YES NO Check IC406 and its peripheral parts.

No picture (AV1, AV2) Is in/output voltages NO of IC401 normal? YES Is output voltages NO at pins 83 and 84 of IC7001 normal? (When inputting NTSC) YES Is output voltages at pins 23 and 25 of IC853 normal? (When inputting NO Check IC401 and its peripheral parts. Check IC7001, IC7002 and their peripheral parts.

No picture apears (AV1) Check Q407~Q410 and their peripheral parts.

Check peripheral parts.

No picture (AV1/AV2)

No picture (Component)

Check IC801 and its peripheral parts.

Is signal input into the pin 13 of IC2001? Check IC853, Q852, Q854, Q857 and their peripheral parts. YES YES

NO

Check IC315, IC316 and its peripheral parts.

except NTSC) YES Are output voltages NO at pin 6 of IC402 and it of IC407 normal? YES Is input voltages NO at pins 13 and 15 of IC801 normal? YES Is output voltages NO at pins 4,5 and 6 of IC801 normal? YES Check IC402, IC407 and their peripheral parts. Check Q802, Q803, Q805, Q806 and their peripheral parts. Check IC801 and its peripheral parts.

Check IC401 and its peripheral parts.

Check the in/output of IC406, IC451 and its peripheral parts.

Is output voltage at pin 18 of IC801 normal? NO Is input voltages at pins 33 and 15 of IC801 normal? NO Check IC406, IC402 and their peripheral parts.

Check in/output voltages of IC406, IC451 and its peripheral parts. Are voltages and waveform of the LCD module connecting connector normal? YES NO Aren't cables break down? Replace cables with new one and check again. YES Replace LCD module with new one and check again.

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