Sharp XG-NV2SB Service Manual page 44

XG-NV2SB
TROUBLE SHOOTING TABLE FOR PC I/F UNIT-3
Checking the S-
VGA's red video
circuit and its
peripheral circuits
Is there signal at pin (13) of IC8004?
Yes
Is there signal at the base of Q29?
Yes
Is there signal at pin (6) of IC8011
Yes
Are there signals at RI1A0 thru -7 and
RI1B0 thru -7 of IC8025?
Yes
Are there signals at R1 thru -10 and
G1 thru -10 of IC8030?
Yes
Are there signals at the bases of Q15
and Q17?
Yes
Are there signals at pins (9) and (11)
of TC2 connector?
Yes
TC2 connector or output PWB faulty.
No
LCP circuitry faulty.
No
Q29 or its peripheral circuit faulty.
No
IC8008 or its peripheral circuit faulty.
No
IC8011 or its peripheral circuit faulty.
IC8020 or its peripheral circuit faulty.
No
IC8025 or its peripheral circuit faulty.
No
IC8030 or its peripheral circuit faulty.
No
Q13, Q14 thru Q17 or their peripheral
parts faulty.
44
Checking the VGA's
red video circuit and
its peripheral
circuits
No
Is there signal at pin (13) of IC8004?
Yes
No
Is there signal at the base of Q29?
Yes
No
Is there signal at pin (6) of IC8011?
Yes
No
Are there signals at VAR0 thru -7 of
IC8020?
Yes
No
Are there signals at RI2A0 thru -7 and
RI2B0 thru -7 of IC8025?
Yes
Check the video
system's red video
circuit and its
peripheral circuits
No
Are there signals at VBR0 thru -7 of
IC8020?
Yes
B
B