Sharp LC-42D43U Service Manual page 30

LC-42D43U
<Component video signal input> No video output (5)
No video output from external input <<INPUT-2>>
Is INPUT-2 selected on the input switching menu screen?
Are component video signals fed to pins 27, 29 and 31 (Y, PB
and PR) of IC501(AV SWITCH)?
Are Y, PB and PR signals sent to pins 60, 59 and 58 of IC501
respectively?
Are component video signals sent to pins 2, 4 and 6 of
TERMINAL_UNIT connector (FC_SC501)?
Are component video signals fed to pins 2, 4 and 6 of
MAIN_UNIT connector (FC_SC1101)?
Are Y, Pb and Pr signals fed to pins L26, J25, J26 of IC8101
(Broadcom) respectively?
Are digital video (LVDS) signals sent from pins 37-42 and 45-48
of IC2602?
Are digital video (COMOS) signal sent from IC8101 (DVODATA 0
~ 23, DVOCLKO, DVODE, DVOHSYNC, DVOVSYNC)?
Check LCD_CONTROL PWB.
YES
YES
YES
YES
YES
YES
YES
NO Select INPUT-2 and the input signal on the input switching menu
screen.
When INPUT-2 cannot be selected since the characters INPUT-2
on the menu screen are gray.
Is the component video signal detection function normal? Check
between 8 pin of J502 and pin 40 of IC501.
NO Check between J502 and each input pin of IC501.
NO Check IC501 and peripheral circuits.
NO Check between IC501 and SC501. (Q501-Q506, etc.)
NO Check the board-to-board cable "FC".
NO Check between SC1101 and IC8801. (Q2210, Q2211, Q2212,
etc.)
NO Check IC2602 and peripheral circuits.
NO Check IC8101 and peripheral circuits.
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