Samsung LED TV UE40C5100QWXXU fuses blown

[dynomo]

Samsung UE40C5100QWXXU led tv. PSU BN44-00353A.

Both fuses on the mains input open circuit. T6.3AH ceramic fuses. No shorts found in circuit at all? Rectifier tested fine. Any idea's?

[ben7]

Re: Samsung LED TV UE40C5100QWXXU fuses blown

Could be a secondary side short, although mostly that will cause the switching transistors to explode.

The switching transistors could be open circuit too. Not only the switching transistors could be broken though! The current sense resistor(s), diodes, even transformer windings!

Pictures?

[tom66]

Re: Samsung LED TV UE40C5100QWXXU fuses blown

A secondary short will not cause a primary failure on a well designed PSU.

The switching transistor, PFC transistor, or the controller ICs could be at fault here.

[ben7]

Re: Samsung LED TV UE40C5100QWXXU fuses blown

A secondary short will not cause a primary failure on a well designed PSU.

The switching transistor, PFC transistor, or the controller ICs could be at fault here.

Ok, correction accepted

[dynomo]

Re: Samsung LED TV UE40C5100QWXXU fuses blown

I have found the problem. Found 8.5k ohms across bridge rectifier + - After some investigation found CP818 / 100pf at 1KV burnt on the side