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3-15
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 sled motor among them.
9-2. SLED MOTOR
9-2-1. Solution
Replace IC401 or IC400 on MAIN board.
9-2-2. How to troubleshoot (Countermeasure)
1) Check the SLDO signal from pin23 of IC401.
If no signal, check 3.3 V (RF) and X400.
2) Check the SLED+ & SLED- from IC400 to CN401 for driving SPINDLE motor. It is about 2.9 Vp-p.
If no signal, check +1.8 V and +5 V for IC400.
3) Check if the FFC cable is solidly connected between CN401 and MD.
4) Check the MD.
If the sled motor is sort-circuit or has any trouble, it can not move the pickup module.
Please check the function after changing another MD.
9-2-3. Service hint (Any picture / Remark)
< Waveform of SLED- & SLED+
for driving SLED motor >
zsR
zsT
< MAIN board top view >
SL-
SL-
pin9 of CN401
pin9 of CN401
SL+
SL+
pin7 of CN401
pin7 of CN401
IC400
IC400
Summary of Contents for CM9750
Page 15: ...2 2 ...
Page 19: ...4 SPEAKER SECTION A60L A60R ...
Page 75: ...3 71 3 72 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Page 77: ...3 75 3 76 2 MAIN P C BOARD TOP VIEW ...
Page 78: ...3 77 3 78 MAIN P C BOARD BOTTOM VIEW ...
Page 79: ...3 79 3 80 3 FRONT P C BOARD TOP VIEW ...
Page 80: ...3 81 3 82 FRONT P C BOARD BOTTOM VIEW ...
Page 81: ...3 83 3 84 4 FRONT_CTRL P C BOARD TOP VIEW BOTTOM VIEW ...