Sharp LC-32HT2U Service Manual page 38

LC-32HT2U
<Composite video signal/S-video signal input> No video output (2)
No video output from external input <<INPUT-2>>
Is INPUT-2 selected on the input switching menu screen?
Is signal fed to each input terminal of IC501 (AV SWITCH)?
<Composite video signal input>
Is video signal fed to pin 3 of IC501?
<S-video signal input>
Are Y and C signals fed to pins 5 and 7 of IC501 respectively?
<Composite video signal input>
Is video signal sent to pin 60 of IC501?
<S-video signal input>
Are Y and C signals sent to pins 60 and 59 of IC501 respec-
tively?
<Composite video signal input>
Is video signal sent to pin 2 of IF_UNIT connector (FC_SC501)?
<S-video signal input>
Are Y and C signals sent to pins 2 and 4 of IF_UNIT connector
(FC_SC501) respectively?
<Composite video signal input>
Is video signal fed to pin 2 of MAIN_UNIT connector
(FC_SC1101)?
<S-video signal input>
Are Y and C signals fed to pins 2 and 4 of MAIN_UNIT connector
(FD_SC1101) respectively?
<Composite video signal input>
Is video signal fed to pin 242 of IC3301 (Trident) via L.P.F. com-
posed of Q2201 and Q2207?
<S-video signal input>
Are Y and C signals fed to pins 242 and 231 of IC3301 (Trident)
via L.P.F. composed of Q2201 and Q2207 and via L.P.F. com-
posed of Q2205 and Q2209 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
Select INPUT-2 and the input signal on the input switching menu
screen.
NO When INPUT-2 cannot be selected since the characters INPUT-3
on the menu screen are gray.
Is the video signal detection function normal? Check between pin
2 of J501and pin 2 of IC501.
Is the S-video signal detection function normal? Check between
pin 6 of J503 and pin 6 of IC501.
NO Check between pin 1 of J501 and pin 3 of IC501.
NO Check between pins 3 and 4 of J503 and pins 5 and 7 of IC501.
NO Check IC501 (AV SWITCH) and peripheral circuits.
NO Check between IC501 and SC501. (Q501, Q502, Q503, Q504,
etc.)
NO Check the board-to-board cable "FC".
NO Check between SC1101and IC3301. (Q2201, Q2207, etc.)/
(Q2205, Q2209, etc.)
NO Check IC3301 and peripheral circuits.
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