Changhong Electric PT4216 Service Manual page 37

TV, AV, S-VIDEO,
all no picture
check U400
TDA8759 horizon
and vertical sync.
And clock ok or
not
check TDA8759 horizon
and vertical sync. And
clock output is normal
or not
No
check TDA8759 power
and peripheral circuit;
change TDA8759
if there is one
state to display
when switch the
source
only AV no no picture only S-
picture
check AV board check S-video
connector
joint well
check UOC3 S-
check UOC3 AV
video I/O is ok or
I/O is ok or not?
input ok, but output
abnormal
check UOC3 and
TDA9178 power,
check UOC3 and
bus;
TDA9178 power,
37
video
check UOC3 31th,41th pin
connector
Yes
not
Input ok,but output
abnormal
bus;
only TV no picture
voltage and peripheral
component is ok or not
check TAD5-
C2F21RW power,
bus and SAW filter
circuit
check and change
TAD5-C2F21RW