3-2
ONE POINT REPAIR GUIDE
1. NO POWER
If the unit doesn’t work by no power problem, repair the set according to the following guide.
1-1. FUSE/ BRIDGE DIODE/ FET
1-1-1. Solution
Please check and replace F901, BD901, BD902, Q902~Q905 on SMPS board.
1-1-2. How to troubleshoot (Countermeasure)
1) Check if the fuse F901 is open or short-circuit.
2) Check if the bridge diode BD901 or BD902 is short-circuit by over current with a digital multimeter.
3) Check if the FET Q902 ~ Q905 is normal or short.
If it is short condition, it’s destroyed. Replace it with a new one.
(Please replace 4 FET at the same time although several FET is OK)
1-1-3. Service hint (Any picture / Remark)
< F901 >
If F901 is not short-circuit,
replace it with a same
speci
fi
cations one.
< Q902 ~ Q905 >
If Q902 ~Q905 is short (pin1-3),
replace it with a new one.
<BD901, BD902 >
If BD901, BD902 is short-circuit,
replace it with a new one.
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 ...