Philips DVP3520 Service Manual page 15

Only DVD disc or only disc except DVD can be played
Only DVD disc, or only disc
except DVD can be Played.
Go
Check the
connection between
24pin and the loader.
Yes
Check whether there is laser
voltage (1.9V for CD and 2.4V
for DVD) on L101 and L102.
Yes
Whether voltage on pin102/pin103 of
U1 varies between 2.4V and 3.3V
(Pin102 =3.3V and Pin103=2.4V for
CD; Pin102=2.4V and Pin103=3.3V
Yes
Check whether pins of U1
and
components
soldered, defected
Yes
Check Q103, Q104
whether in
condition
Yes
Change U1 or the loader.
FFC
No
peripheral
are badly
No
good
5-5
Check the loaded circuit
No
Check the solder status on U1 and
peripheral components
No
check if bad solder exist on U1 and
peripheral components
No
Replace the bad spare parts
Correct connection
Trouble shooting chart