Samsung LN40B550K1F no power

[PeteTait]

I acquired this tv with out any knowledge of what the problem was. I plugged in and had no power. Opened it up checked the caps and fuses. Caps looked good. First fuse closes to power plug was good. Second fuse was blown. I swapped it and it plugged the set in and it immediately blew. Where do i look next?? attached is a picture of the board with the fuse that is blown circled in red.

[maxvalutech]

Re: Samsung LN40B550K1F no power

I'll supply this circuit diagram and hopefully the real experts will chime in for you.

[tvtimmy]

Re: Samsung LN40B550K1F no power

Check these parts first. I like the Rod Farva icon. Only 9 days till supertroopers 2!

[PeteTait]

Re: Samsung LN40B550K1F no power

Well i am going to print the circuit diagram and start circling the part numbers that were recommended to check. Then find them on the board and check.

[freakaftr8]

Re: Samsung LN40B550K1F no power

Most likely QP801 and 802S shorted. Shoddy soldering casused this most likely. Thanks ROHS lead free solder!

[nomoresonys]

Re: Samsung LN40B550K1F no power

Check your diodes and transistors too, see if any are bad. Testing video https://www.youtube.com/watch?v=i4jTHhXuKLA

[neilc6]

Re: Samsung LN40B550K1F no power

+1 for shorted transistors. See my post here https://www.badcaps.net/forum/showthread.php?t=67743