Sharp TU-GA1U-S - Watching TV (Continued); Changing Channels

27
TU-GA1U-S
TU-GAD
TROUBLE SHOOTING TABLE (Continued)
No video output (1)
External input in trouble <Video 1>
Is Video 1 selected in the input switching
menu screen?
Are there digital video signal outputs at pins
(43), (44), (46), (47), (48), (49), (54), (55)
and (58) of IC400?
Are there digital video signal inputs at pins (51) thru (78) and (7) thru (10) of IC3201? (Signal pins only)
Are there digital video signal outputs at pins (39) thru (49) of IC3201? (Signal pins only)
Are there digital video signal outputs at pins (3) thru (16) of SC3200? (Signal pins only)
<Composite video signal input> Is there main video signal output at pin (60) of IC3800, or sub video signal output at pin (56)?
<Composite video signal input>
Is there signal input at pin (65)?
Is there signal input at each input pin of
IC3800 (AV SWITCH)?
Select Video 1 and the input signal in the input
switching menu screen.
If signal name is in gray and not selectable
in the menu screen
Check between pin (4) of J1103 and pin
(65) of IC3800.
Is composite video signal detection
functioning normally? Check between
J1103 and pin (9) of IC1102.
Is there signal input at each input pin of
IC400 (MAIN VIDEO DEC)?
<Composite video signal input>
Is there signal input at pin (85)?
Check IC 400 (MAIN VIDEO DEC) and its
peripheral circuits.
Check between IC401 and IC400.
External input in trouble <Video 2>
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
Check between IC501 and IC500.
NO
NO
Are there digital video signal outputs at pins
(43), (44), (46), (47), (48), (49), (54), (55)
and (58) of IC500?
Check IC500 (SUB VIDEO DEC) and its
peripheral circuits.
NO
Replace the main PWB, or check between
IC400/IC500 and IC3201.
NO
Check IC3201 (LV DSTx) and its peripheral
circuits.
Check between IC3201 and SC3200.
NO
NO
Select Video 2 and the input signal in the
input switching menu screen.
If signal name is in gray and not selectable
in the menu screen
Check between pin (8) of J1105 and pin
(71) of IC3800.
Check IC3800 (AV SWITCH) and its
peripheral circuits.
Is composite video signal detection
functioning normally? Check between
J1105 and pin (11) of IC1102.
NO
NO
NO
<Composite video signal input> Is there main video signal input at pin (2) of IC401, or sub video signal input at pin (2) of IC
501?
Check between IC3800 and IC401/IC501.
NO
No problem up to the main PWB. Check TMDS PWB.
Is Video 2 selected in the input switching
menu screen?
<Composite video signal input>
Is there signal input at pin (71)?
Is there signal input at each input pin of
IC3800 (AV SWITCH)?
YES
<Composite video signal> input
<Main video signal>
Is there signal input at each input pin of
IC500 (SUB VIDEO DEC)?
<Composite video signal input>
Is there signal input at pin (85)?
<Sub video signal>