4-20

No video picture, no sound.
Change CE10, and D3.
No video picture,
no sound.
Check whether there is
27MHz si
g
nal out
p
ut.
Check if there is 128MHz
signal output from R59.
Check the loaded circuit
Crystal oscillator Y1 and
peripheral components
are defected or eroded.
Check whether
short-circuit or bad
solder on U7
No
No
No
No
No Yes
Yes
Yes
Yes
Yes
Reconnect the component in
short-circuit
Check U2.
Yes
No
27M waveform
SDRAM(R59 SDCLK) waveform
Check whether all the voltages
from the power board to the
decoder board are normal.
CVBS(R85 point) waveform

Trouble shooting chart

Go
Check if the reset circuit consisting
of CE10, and D3 is normal (at a
high level for tens of milliseconds,
then constantl
y
at 0V
)
.
Check if short-circuit and bad
solder exist on Pin Y1

Remark: Trouble shooting chart for

DVP3156/XX, DVP3166
(
K
)
/XX