Sharp LC-15B2EA, Service Manual

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12
LC-15B2EA
TROUBLE SHOOTING TABLE
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Check all the settings microprocessor's adjust process menu.
Do F1 and F2 function?
Are T3701's secondary o31V, +22V, +9V, +5V and -8V normal?
Remove F1 and F2 and check the load side. Is there short-circuiting?
Is there short-circuiting of T3701 primary side periphery, Q3700, Q3701 and S4701?
Replace F1 and F2.
Check S4701 and connection cable.
Is T3701's primary oscillator waveform normal?
Check T3701's secondary load.
Yes
Yes
No
No
No No
Yes
Check J3702 periphery and connection cable.
Yes
Back light lamp failure to light up
Replace F6500 and F6501.
Is the pin (34) of IC1201 in the "H" state?
Is the primary side of T6500~T6503 periphery short-circuiting?
Replace the back light lamp with new one and check again.
Yes Yes
No No
Yes
Check the OFL1 line, IC1201 and their peripheral parts.
Check T6500~T6503, Q6500~Q6505 and connection cable.