Sharp LC-32HT2U Service Manual page 37

<Composite video signal input> No video output (1)
No video output from external input <<INPUT-1>>
Is INPUT-1 selected on the input switching menu screen?
Is video signal fed to pin 65 of IC501 (AV SWITCH)?
Is video signal sent to pin 60 of IC501?
Is video signal sent to pin 2 of IF_UNIT connector (FC_SC501)?
Is video signal fed to pin 2 of MAIN_UNIT connector
(FC_SC1101)?
Is video signal fed to pin 242 of IC3301 (Trident) via L.P.F. com-
posed of Q2201 and Q2207?
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
Select INPUT-1 and the input signal on the input switching menu
screen.
NO When INPUT-1 cannot be selected since the characters INPUT-1
on the menu screen are gray.
Is the video signal detection function normal?
Check between pin 5 of J501 and pin 70 of IC501.
NO Check between pin 4 of J501 and pin 65 of IC501.
NO Check IC501 (AV SWITCH) and peripheral circuits.
NO Check between IC501 and SC501. (Q501, Q502, etc.)
NO Check the board-to-board cable "FC".
NO Check between IC501 and IC3301. (Q2201, Q2207, etc.)
NO Check IC3301 and peripheral circuits.
6 – 4
LC-32HT2U