Sharp TU-45GAD, Service Manual

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42
TU-GD10U-T
TU-45GAD/T
LC-45GX6U/D/T
TROUBLE SHOOTING TABLE
(Continued)
YES YES YES YES YES
YES
NO NO NO NO
YES YES
NO NO NO NO NO
YES
NO
YES
<Signals>
No video output (1)
<Composite video signal> input
External input in trouble <VIDEO1>
Is VIDEO1 selected in the input switching menu screen?
Is composite video signal detection functioning normally? Check between J1
103
and pin (9) of IC1
102.
Check between pin (4) of J1
103 and pin (65)
of IC3800. Select VIDEO1 and the input signal in the input switching menu screen. If signal name is gray and not selectable in the menu screen
Check IC3800 (A
V SWITCH) and the
peripheral circuits.
< Composite video signal input > Is the signal input to pin (1)? Is the signal input to each input terminal of IC3800 (A
V SWITCH)?
Is the signal input to each input terminal of IC403 (MAIN VIDEO DEC)?
Are there digital video signal outputs at pins (56)~(69) and (92)~(106) of IC403?
Is the digital video signal input to pins (51) to (100) and pins (1) to (10) of IC3201? (Check the signal terminals only
.)
Is the digital video signal output from pins (39) to (49) of IC3201? (Check the signal terminals only
.)
< Composite video signal input >
Are there MAIN VIDEO signal output at pin (60) of IC3800 and SUB VIDEO signal output at pin (5
6)?
< Composite video signal input > Is the main video signal input to pin (2) of IC402 and sub video signal input to pin (2) of IC
501?
Check between IC3800 and IC402/IC501.
<MAIN VIDEO>
<SUB VIDEO>
Check between IC402 and IC403.
Is the signal input to each input terminal of IC502 (SUB VIDEO DEC)?
< Composite video signal input > Is the signal input to pin (135)?
< Composite video signal input > Is the signal input to pin (135)?
Check between IC501 and IC502.
Check IC403 (MAIN VIDEO DEC) and the peripheral circuits.
Are there digital video signal outputs at pins (56)~(69) and (92)~(106) of IC502?
Check IC502 (SUB VIDEO CHROMA) and the peripheral circuits. Replace the main PWB, or check between IC403/IC502 and IC3201. Check IC3201 (L
VDS
Tx) and the
peripheral circuits.
Is the digital video signal output from pins (3) to (16) of SC3200? (Check the signal terminals only
.)
Check between IC3201 and SC3200.
No abnormality is found up to main PWB. Check the
TMDS PWB.