SHARP LC20B2E
Instrukcja Serwisowa

LC-20B2E

picture, No sound Fluorecent lamp failure to light up

Check all the settings microprocessor's adjust process menu.

Remove F2 F4 and No Is there short-circuiting?

Do F4 check the load side. Replace F2 and F4. Does F1 function?

Yes
P901 and Is pin (34) of in Check the OFL1 line, IC1201 connection cable. the "H" state? and their peripheral parts. outputs, +38V, +16V, +9V, T701 primary side periphery, +5V -8V normal? Q751, Q753 and P901. Are T701's secondary Is there short-circuiting of No

No Yes No
peripheral parts. waveform normal?

Is T701's primary oscillator Check Q3603 and their Is the Q3603 short-circuiting?

Yes
Check T701's secondary T5701 T5702 primary Q5701~Q5703 and load.

No Is there short-circuiting of Check T5701, T5702,
connection cable. side periphery, Q751~Q753.

TROUBLE SHOOTING TABLE

12
Replace the fluorecent lamp with new one and check again.

Yes