Sharp LC-32HT2U Service Manual page 40

LC-32HT2U
<Component video signal input> No video output (3)
No video output from external input <<INPUT-1>>
Is INPUT-1 selected on the input switching menu screen?
Are component video signals fed to pins 21, 23 and 25 (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 IF_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 246, 232 and 225 of IC3301
(Trident) respectively?
Are digital video (LVDS) signals sent from pins 28-31 and 34-37
of IC3301?
Check LCD_CONTROL PWB.
YES
YES
YES
YES
YES
YES
YES
NO Select INPUT-1 and the input signal on the input switching menu
screen.
When INPUT-1 cannot be selected since the characters INPUT-1
on the menu screen are gray.
Is the component video signal detection function normal? Check
between pin 8 of J501 and pin 38 of IC501.
NO Check between J1501 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 IC3301. (Q2202, Q2203, Q2206,
etc.)
NO Check IC3301 and peripheral circuits.
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