Service manual

29
LC-20C3U-S
No picture and sound
Yes
No
No
Yes
Yes
No
Yes
No
Fluorescent lamp
Yes
No
Yes
No
Yes
No
Yes
Yes
Replace F6700, F6701,
F6702, F6703, and F6704.
Check the line, IC1201 and
its peripheral parts.
Check Q6700 - 6714, T6700
- 6709 and their peripheral
parts.
Does F6700, F6701,
F6702, F6703, and
F6704 function?
Is Pin (34) of IC1201 at
“H”?
Are the oscillation waveforms
at the primary side of T6700,
T6702, T6704, T6706, and
T6708 as specified?
Replace the fluorescent lamp
and check the oscillation
waveform again.
Do F3701and F3702
function?
Are secondary outputs
(+34V, +9V, +5V, -7V, -20V)
of T3701 as specified?
Are the oscillation waveform
at T3701’s primary side as
specified?
Check the secondary-side
load of T3701.
Disconnect F3701and
F3702. Is the load side
short-circuited?
Is any of T3701
’s primary
side, Q3700 and S4701 short-
circuited?
Check J3701, its peripheral
parts and connection cable.
Replace F3701 and F3702.
Check S4701 and
connection cable.
Check all the settings on the microprocessor
’s adjust process menu.
TROUBLE SHOOTING TABLE (Continued)