One Point Repair Guide; Power - LG CM9750 Service Manual

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
specifi cations one.

ONE POINT REPAIR GUIDE

<BD901, BD902 >
If BD901, BD902 is short-circuit,
replace it with a new one.
3-2
< Q902 ~ Q905 >
If Q902 ~Q905 is short (pin1-3),
replace it with a new one.