Service manual

31
LC-20C3U-S
TROUBLE SHOOTING TABLE (Continued)
No sound
from
speakers
Yes
No
No sound
No
Yes
No
Yes
Yes
No
No
Yes
No sound
from
headphone
Yes
No
No sound
from output
line
Yes
No
No
Yes
TV sound
failure
Yes
No
No
Yes
Is pin (53) ,(54)
of IC2001 at
“L”?
Check all the settings on the microprocessor
’s adjust process menu.
Are outputs at
pins (1) and (7)
of IC3301,
IC3302, IC3303,
IC3508 as
specified?
Are inputs at pins
(2) and (4) as well
as outputs at pins
(8) and (12), all of
IC3305, and
IC3307 as
specified?
Muting effect is
on. Check the
PSMUTE and 2
line.
Check IC3301,
IC3302, IC3303,
IC3583 and
their peripheral
parts.
Are input and
output of
IC3304 as
specified?
Check IC3304
and its
peripheral parts.
Are input and
output of
IC3401 as
specified?
Check IC3401
and its
peripheral parts.
Check the line
in question,
IC3301,IC3307
and its
peripheral parts.
Check the
speakers and
their peripheral
parts.
Is pin (55) of
IC2001 at “L”?
Check the
headphone and
its peripheral
parts.
Check Q2007,
J3500, harness
and their
peripheral parts.
Is pin (58) of
IC2001 at “L”?
Are outputs at
pins (14) and
(15) of IC3501
as specified?
Check the line
in question.
Check the
LMUTE line.
Check IC3501,
IC3502, IC3304
and their
peripheral
Is output at Pins
(15) and (16) of
tuner as
specified?
Is input at pin
(67) of IC3304
as specified?
Check IC3304,
X3301 and
their peripheral
parts.
Check the
tuner and its
peripheral
parts.
Check Q3201,
Q3202 and
their peripheral
parts.