Sharp LC-20B2UA, Service Manual

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23
LC-20B2UA
TROUBLE SHOOTING TABLE
(Continued)
Check all the settings on the microprocessor
’s
adjust process menu.
No picture
No picture at all
Yes
No
Are inputs and outputs of IC801 as specified?
Does the LCD controller test pattern appear?
Does the video decoder test pattern appear?
Check IC402 and its peripheral parts. Check IC1201, its peripheral circuits and the LCD panel. Check IC801 and its peripheral circuits.
Yes
No No
No VIDEO 1 or 2 output
Yes
No
Are inputs and outputs of IC402 as specified?
Check IC402 and its peripheral parts. Check IC7001 and its peripheral parts.
No
Is input at Pin (73) of IC801 as specified?
Check IC801, A
V1 line and
their peripheral parts.
Yes
No
Are input and output of IC7001 as specified?
Check IC7202 and its peripheral parts.
Yes
No
Are input and output of IC7202 as specified?
No
Are pin (67) of IC2001 at “H”?
No S VIDEO output
Yes
Yes
Are pins (2) and (12) of IC7101 60th at “H”?
No
Are inputs at Pins (71) and (72) of IC801 as specified?
Check SC3405, SY line, SC line and peripheral parts.
No COMPONENT output
No
Is input at Pins (4), (5), (6) and (75) of IC801 as specified?
Check J3404, DVD-Y
line,
PB line, PR line and peripheral parts.
No TV output
Yes
No
Are voltages at Pins (6), (7) and (9) of tuner as specified?
Check the power line.
Yes
No
Is output at Pin (19) of tuner as specified?
Check the tuner and its peripheral parts.
No
Is input at Pin (3) of IC402 as specified?
Check the line in question.
Yes
Check IC402 and its peripheral parts.
Yes
No
Are Pins (2) and (4) of IC402 at “H” and “L” respectively?
Are Pins (65) and (66) of IC2001 at “H” and “L” respectively?
Yes
Check the line in question.
Check pin (88) of IC2001 or the SSW line.