Service manual

CD-DK890N
7 – 2
Although a CD is inserted and the cover is closed,
"NO DISC" is displayed.
(1) Focus-RF system check.
Press the Tray1 CD Eject Button without inserting a disc, and try
starting the playback operation.
Figure 1
IC1
IC1
1
22
23
2
FDO
TDO
1. Does the pickup move to the PICKUP-IN Switch (NSW1)
position ?
No Sled motor (NM2).
Yes
2. Does the focus (lens) move up and down ?
(Waveform drawing Figure 1)
No Check the focus peripheral circuit.
Yes
3. Is the laser lit ? No Check the laser diode driver Q1 peripheral circuit.
Yes
4. Is the turntable rotating ? No Spindle motor (NM1).
When a disc is loaded, start playback operation.
1. Is focus servo activated ?
(Waveform drawing Figure 2)
No Pins 5~9, 11, 18 19 and 22 on IC1
Check the laser diode driver Q1 peripheral circuit.
Yes
2. Is the RF waveform normal ?
(Waveform drawing Figure 3)
No If the level is not normal.
Figure 2
IC1
IC1
22
16
3
1
FDO
TE
Figure 3
IC1
2
RFOUT
4