Philips PET717 Service Manual page 22

No video picture, no sound.
No video picture,
Check whether all the voltages
from the IC U1(OZ518) to the
decoder IC are normal.
Check if the reset circuit consisting of
R86,R87,R89,R90,C86,C88,C89,D14 and
Q17 is normal (at a low level for tens of
milliseconds, then constantly at high
Check whether there is
27MHz signal output.
Check if there is 135MHz
signal output on R129.
Yes
Check if short-circuit and
bad solder exist on Pin 136
of U3
Yes
Reconnect the component in
short-circuit
no sound.
Yes
Yes
Yes
SDRAM(R99 SDCLK) waveform
5-8
No
Check the loaded circuit
No
Replace
R86,R87,R89,R90,C86,C88,C89,D14
Crystal oscillator Y2 and
No
peripheral components
are defected or eroded.
Check whether
No
short-circuit or bad
solder on U6,U7
No
Yes
Trouble shooting chart
CVBS waveform
27Mhz waveform
No
Check U3.