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3-19
ONE POINT REPAIR GUIDE
5. 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
SPINDLE MOTOR among them.
5-1. SPINDLE MOTOR
5-1-1. Solution
Please check and replace IC407, IC408 on MAIN board.
5-1-2. How to troubleshoot (Countermeasure)
1) Check the SPDO signal from Pin16 of IC407.
If no signal, check 3.3V(RF) and X402.
2) Check the SP- & SP+ from IC408 to CN405 for driving SPinDLE motor. It is about 3.6 Vp-p.
If no signal, check +1.8 V and +5 V for IC408.
3) Check if the FFC cable is solidly connected between CN405 and MD.
4) Check the MD.
If the spindle motor is sort-circuit or has any trouble, it can not rotate CD discs.
Please check the function after changing another MD.
5-1-3. Service hint (Any picture / Remark)
zwRGGju[W\
zwTGju[W\
G
ZU]} T
z w R
_GGju[W\
z w T
`GGju[W\
pj[W_
< Waveform of SP- & SP+
for driving SPINDLE motor >
< Signal check point >
Содержание CM7420
Страница 13: ...1 12 MEMO ...
Страница 15: ...2 2 MEMO ...
Страница 19: ...A60 4 SPEAKER SECTION FRONT SPEAKER CMS7520F ...
Страница 82: ...3 79 3 80 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Страница 84: ...3 83 3 84 2 MAIN P C BOARD TOP VIEW ...
Страница 85: ...3 85 3 86 MAIN P C BOARD BOTTOM VIEW ...
Страница 86: ...3 87 3 88 3 FRONT_VFD P C BOARD TOP VIEW BOTTOM VIEW ...
Страница 87: ...3 89 3 90 4 FRONT_MIC PORTABLE P C BOARD TOP VIEW BOTTOM VIEW ...
Страница 88: ...3 91 3 92 5 FRONT_VOLUME P C BOARD TOP VIEW ...
Страница 89: ...3 93 3 94 FRONT_VOLUME P C BOARD BOTTOM VIEW ...