Sharp XG-NV5XB, Service Manual

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42
XG-NV5XB
TROUBLE SHOOTING TABLE FOR PC I/F UNIT-3
Yes
Yes
No No
Is there signal at pin (13) of IC8004?
Is there signal at pin (13) of IC8004?
LCP circuitry faulty.
B
B
Yes
Yes
No No
Is there signal at the base of Q8008?
Is there signal at the base of Q8008?
IC8004 or its peripheral circuit faulty.
Yes
Yes
Yes
No No
Is there signal at pin (6) of IC8011
Yes
Are there signals at TL44 and TL46?
Is there signal at pin (6) of IC8011?
Q8008 and Q8009 or there peripheral
circuit faulty.
Yes
No No
Are there signals at Pins (21) thru
(27) and (33) thru (40) of IC8011? Are there signals at Pins (112) thru
(119) of IC8020?
IC8011 or its peripheral circuit faulty.
Yes
No
Are there signals at Pins (69) thru
(73) and (189) thru (192) of IC8020?
IC8020 or its peripheral circuit faulty.
Yes
Yes
No
Are there signals at pins (9) and (10)
of CON4 (P8405) connector?
Are there signals at pins (1) thru (10)
of IC8051?
IC8051 or their peripheral parts faulty.
No
IC8029 or its peripheral circuit faulty.
No
IC8025 or its peripheral circuit faulty.
CON4 (P8405) connector or output
PWB faulty.
Checking the S-
VGA's red video
circuit and its
peripheral circuits Checking the VGA's
red video circuit and
its peripheral
circuits
Yes
No
Are there signals at Pins (112) thru
(119) of IC8020?
Check the video
system's red video
circuit and its
peripheral circuits