Samsung HP-S4253, Service Manual

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Troubleshooting
Samsung Electronics 6-7
6-2-6 Main SMPS Troubleshooting
Breck Down
Stand-By output
Normal
Operation?
Fuse
(F101, F103)
OPEN?
Item
confirmation
1-3
Please return back the
broken Power supply and
request a service to
SANKEN
Item
confirmation
1~3
Item
confirmation
4
Result
ITEM
Stand-By Circuit Problems
Consider the Short of Input line or
Bridge Diode section.
Consider a cause of the breakage
Confirm OV. UV of each Output
1. Is the Drain-Source of Q8201, Q8202, Q8205 shorten? → Breakage of PFC
2. Is the Drain-Source of Q8301, Q8302 shorten?
→ Breakage of Low Voltage circuit
3. Is the Drain-Source of Qs401 shorten? → Breakage of Va circuit.
4. CN302[5pin] is 'H' and Cn802[6pin] is 'L'? {Micom Board} → Stopped by the wrong level of output voltage
* Please return back the broken Power Supply
- It could be with difficulty finding the cause if you handle it first
- Unless you return back it when the broken Power supply has only a little damage. it could make the other problem.
Sequence Circuit Problem