Read Sharp LC-15L1E (serv.man8) Service Manual online
28
LC-15L1E
»
TV receiver (RX) side fault-finding flowchart with no link
Not serviceable
IC1704 failure
OK
OK
OK
A. No display
YES
YES
YES
YES
NO
NO
NO
NO
NO
YES
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
OK
No link
Check the microcomputer operation using terminal software.
OK
OK
1
Is normal +9V available at pins
(1)-(3) of CN2?
B. No second time Version display
C. MPEG setup OK is not
displayed.
D. No display after APOLL2
startup
E. All displays are normal.
1
Using a spectrum analyzer
or the like, check that output
signal has RF waveform.
2
Check that the cable
connecting CN200 and
UNT1700 has no
interference or damage.
3
Replacement of UNT1700
did not help recover normal
operation?.
4
Check pins (40)-(43) of
IC704 and the peripheries.
5
Check CN200 and the
peripheries.
2
Is normal +3.3V available at each
of the following pins of IC1701?
(1), (8), (31), (37), (44), (54),
(67), (73), (80), (90), (103),
(109), (116), (126), (133) and
(139)
1
Check IC1701 and the periphery.
3
Go to the step E.
2
.
1
Is normal +1.5V available at
both ends of L6000, and
+3.3V at both ends of L6001?
3
Is signal waveform normal at pin
(44) of IC1100?
1
Check IC1100 and the periphery.
4
Check the following connections.
Between pin (23) of IC1100 and
pin (21) of IC704
Between pin (24) of IC1100 and
pin (23) of IC704
2
Is output normal at the following
pins of IC1100?
(1), (11), (20), (28) and (30): +3.3V
2
Is normal +3.3V output
available at pin (4) of IC906?
3
Is output signal waveform
normal at pin (13) of IC704?
4
Is normal +3.3V output
available at pin (4) of IC706?
6
Check IC704, Q705 and their
peripheries.
7
Check IC902 and the periphery.
8
Is normal +1.5V available at
TP902?
9
Is normal +3.3V available at
TP900?
0
Is normal +5.0V output
available at pin (4) of IC907?
q
Check IC1500 periphery.
Check for
connector
damage or cable
disconnection.
Check IC906
periphery.
Go to the step
A.
9
.
Go to the step
A.
8
.
Check L6000
and L6001.
Go to the
step A.
9
.
Replace the
cable.
Check FL701
periphery.
Check IC706
periphery.
Check Q904
periphery.
Check Q902
periphery.
Check IC1501
and Q903
peripheries. Go
to the step B.
1
.
