Sharp LC 20M4U, Service Manual

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LC-20M4U
14
TROUBLE SHOOTING TABLE
(Continued)
No picture
Check all the settings microprocessor's adjust process menu.
Is in/output of IC801 normal?
Is in/output of IC1201 normal?
Check IC801 and its peripheral parts. Check IC1201 and its peripheral parts.
Check IC402 and its peripheral parts.
Check IC801, AV1 line and its peripheral parts.
Check LCD panel voltage and waveform.
Yes Yes
No No
No picture at all
Is in/output of IC402 normal? Is input at pin (73) of IC801 normal?
Yes
No No
No VIDEO 1 and VIDEO 2 output
Is input at pin (1) of IC402 normal? Is the pins (2) and (4) of IC402 at "L" state?
Check the its line. Check the its line.
Check IC402 and its peripheral parts.
Is the pins (65) and (66) of IC2001 at "L" state?
Yes No
No
Yes Yes
No VIDEO 1 output
Is input at pin (5) of IC402 normal?
Is the pin (4) of IC402 in the "H" state?
Check the its line. Check the its line.
Yes
Yes
No No
No VIDEO 2 output
Check IC402 and its peripheral parts.
Is the pin (68) of IC2001 in the "H" state?
No picture
Check all the settings microprocessor's adjust process menu.
Is input at pins (71) and (72) of IC801 normal?
No S-VIDEO output
Check SC401, SY-line, SC-line and their peripheral parts.
No
Is input at pins (4), (5), (6
) and (
75)
of
IC801
as specified?
No COMPONENT output
Check J4403, J4404, J4405, DVD-Y line, PB line, PR line and their peripheral parts.
No