3-12
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
NO OPERATION OF MD
When no sound output in the CD function, you can not listen to music reading data from a CD disc
if the servo motors in MD don’t work. This step is for checking the tray open/close motor among them.
5-3. TRAY OPEN/ CLOSE MOTOR
5-3-1. Solution
Replace IC401 or IC400 on MAIN board.
5-3-2. How to troubleshoot (Countermeasure)
1) Check MOT_OPEN & MOT_CLOSE signals from pin P5 & L4 of IC501 to IC400.
If no signal, check M_5V for IC400.
2) Check LOAD ± from IC400 to CN401 for driving the tray open/close motor. It is about 3.85 Vp-p.
If no signal, check DVCC_3.3V to IC401. If it has any trouble, replace it with a new one.
3) Check if the FFC cable is solidly connected between CN401 and MD.
4) Check the MD.
If the tray motor is short-circuit or has any trouble, it can not open or close the tray.
Please check the function after changing another MD.
5-3-3. Service hint (Any picture / Remark)
tv{jsvzl
tv{vwlu
svROylkP
sv T
< Waveform for driving TRAY open/close motor >
< MAIN board top view >
< MAIN board bottom view >
LO+
LO+
pin4 to CN401
pin4 to CN401
LO-
LO-
pin2 to CN401
pin2 to CN401
CN401
CN401
IC400
IC400