Sharp XG-MB70X, Service Manual

Page: 41 / 161

41
XG-MB70X
Checking of Video input
Send composite VIDEO
signals to INPUT3. Use keys
on the main unit or remote
control to select INPUT3.
Is picture signal input to pin
(1) of IC3103? Check the VIDEO-IN signal line
of Q3104 and soldering of
J3101.
Is input signal SECAM?
Check the peripheral circuits of
C3103 and color system
malfunctions.
Are picture signals input to
pins (39) and (41) of IC3103? Do pulse-shaped waveforms appear
at pins (15) and (16) of IC3105?
Check IC3105 and peripheral
circuits.
Are picture signals output
from pins (21), (22) and (23)
of IC3103?
Do pulse-shaped waveforms appear
at pins (13) and (14) of IC3103?
Check IC3103 and peripheral
circuits.
Are picture signals input to
pins (67), (68) and (68), and
output from pins (35), (37)
and (38) of IC3101?
Do pulse-shaped waveforms appear
at pins (55) and (56) of IC3101?
Check IC3101 and peripheral
circuits.
The I2C bus line does
not function normally.
Check IC2201, IC2003,
IC2005, IC2006, IC2007
and their peripheral
circuits.
Check if IC connected to
I2CBUS functions
normally.
NO
YES
YES
NO
NO
NO
YES
YES
NO
NO
YES
YES
NO
NO
YES
YES
1
2
Checking of
S-Video input
Send S terminal (Y and C) signals to INPUT4.
Use keys on the main unit or remote control to
select INPUT4.
Are picture signals output from pins (43) and
(44) of IC3103?
Check the soldering of J3101.
NO
YES
2