Service manual

CD-SW250DVD
7 – 3
• “No Disc” is displayed during CD playback (when DVD is playable) ... When CD laser does not light up.
Is control signal output from pin 17 of IC 3101 ? No Check and replace IC3101.
Yes
Is voltage of 5 V applied to the emitter of Q3104 ? No Check S5V line.
Yes
Is voltage of approx. 1.9 V supplied to pin 6 of CN3001 ? No Check around Q3102 and Q3104.
Yes
Check co nnection of optical pickup cables.
If no a bnormality is detected, replace optical pickup mechanism
unit.
Note: The laser diode is easily damaged by static electricity.
Carefully check static electricity and electric leak of the measuring
instrument.
Put a disc on the DISC tray.
Yes
Disc normally loaded?
Yes
Check loading switch.
No
Is RF signal level output from pin 17 of
CN3001 normal ?
Yes
Is objective lens of optical pickups clean?
No
Yes
Replace Servo PWB.
Replace optical pickup mechanism unit.
No
Refer to "Video is not output normally" and
"Audio is not output normally".
Yes
Both video and audio do not operate normally.