SHARP LC-20SH1E
Manual de Servicio

picture and No sound Back lamp failure to light up

Remove F7701 and Check Q6700Do fuse F6700Is there any short No

F6704 function? circuit in INV +B Replace F7701. function? Is there shortperipheral parts for line? circuit? short circuiting. Yes Check the OFL1 Are T7701 secondary Is there any shortAre the pins (40)

No Yes
Do fuse F7701 check the load side. Q6716 and their

Yes

Yes output at C7720, No OFL2 line, C7721, C7722, C7723 IC1201 and their and C7725 voltage peripheral parts.

circuit in T7701 and (138) of IC1201

primary side in the "H" state? periphery? normal? Yes Are outputs of Check the OFL line,

Is Q7702 base No voltage at "L" state?

Yes No Q3600, Is T7701 primary Q3600 and Q3601

No
all output Check IC7702,

switching waveform at Yes in the "L" state? their peripheral voltage line for IC7704 and their pin (1) of IC7701 parts. short circuit. peripheral parts. normal? Yes

No No Is the pins (4) and Check Q6700(7) of T6700-T6704 Q6716 and their Check IC7701 and Yes
Replace the back Is the pin (10) of No light lamp with new T6700-T6704 one and check normal? again.

its peripheral parts. normal? peripheral parts.

TROUBLE SHOOTING TABLE

21
Yes
Check the error amp circuit D6702D6711, Q6706, Q6713, Q6717 and their peripheral parts.

LC-20SH1E