Philips DVP3136/94 Service Manual page 16

Disc cannot be read .
Disc cannot be read.
Check the FFC connection
between 24P and the loader.
Check whether there is laser
voltage (2.3V for DVD and 1.9V
for CD) on Collector of Q2 &Q3
Check
peripheral components are
eroded or badly soldered.
Yes
Check if there is RFO signal on
pin10 of CN2. (The normal RFO
signal is a clear reticulated wave)
Check the connection
between U1
Replace U1 or loader.
Yes
Yes
Yes
U1, U7, and
Yes
Yes
4-4
No
Check the loaded circuit
1.Check voltage on pin 100 of U1 varies
between 0 and 3.3V:
No
3.3V for CD
0V for DVD
2.Check whether peripheral components
are eroded or defect
No
Re-solder or replace the defective parts
No
Check U1 and peripheral components
No
Correct connection
Trouble shooting chart