4-4
Disc cannot be read
.
No
Yes
No
Yes
No
Yes
Yes
No
No
Yes
Disc cannot be read.
Check the loaded circuit
1. Check voltage on pin 44 of U1 varies
between 0 and 3.3V:
Æ
3.3V for VCD
Æ
0V for DVD
2.Check whether peripheral components
are eroded or defect
Check the FFC
connection between 24P
and the loader.
Check U1 and peripheral components
Re-solder or replace the defective parts
Check the connection
between U1
Correct connection
Replace U1 or loader.
Yes
Check whether there is laser
voltage (1.9V for VCD and
2.3V for DVD) on Collector of
Q7 &Q8
Check if there is RFO signal
on pin17 of CN3. (The
normal RFO signal is a clear
reticulated wave)
Check U1, U2, and
peripheral components
are eroded or badly
soldered.
Trouble shooting chart