Sharp 25VT-J100 Service Manual page 19

NO SOUND
NO Does waveform appear
at pin (54) of IC401 ?
Check IC401 and
adjacent parts
Does waveform appear
at pin (8) of IC351 ?
NO Does approx. 11V appear
at pin (3) of IC351 ?
Check D725, R327,
C725, C726, FB726
Check IC351 and
adjacent parts.
NO PLAYBACK PICTURE
Is there a signal at pin
(39) of IC401 ?
Check IC401 and
adjacent parts as same
as "NO PICTURE".
FLOW CHART NO.2-5
YES
NO
Check IC401, and
adjacent parts.
YES
YES
FLOW CHART NO.2-6
NO Check the VCR:
TROUBLESHOOTI
NG "NO
YES
PLAYBACK".
NO PLAYBACK SOUND
Is there a signal at pin
(55) of IC401 ?
Check the TV:
TROUBLESHOOTING
"NO SOUND".
INFRARED R/C TROUBLESHOOTING
No operation is possible from the
infrared remote control.
Does the infrared remote control NO
function ?
YES
NO
Is 5V applied at pin (2) of the
remote control receiver ?
YES
Is "L" pulse given out of pin (1) of NO
the receiver and received at pin (4)
of IC2001, when the infrared remote
control is activated ?
YES
Is fluorescent lighting enough away NO
from the set ?
YES
Is there short-circuit in the key input NO
or IC2001 ?
YES
Check IC2001
FLOW CHART NO.2-7
Check the VCR:
NO
TROUBLESHOOTI
NG "NO SOUND".
YES
FLOW CHART NO.2-8
Replace the infrared remote control
as required.
Check the 5V and GND lines.
Check pin (10) of IC2001 and /or
receiver.
Reposition the set not to be
exposed to strong light.
Check key input terminals.