Samsung BN44-00194A power supply dead

[london-freddie]

helping a friend with a dead Samsung PS42Q96HDX/XEU plasma tv
Dead no sign of life at all
Apparently just went off whilst watching tv

Power board is BN44-00194A
checked 4 fuses on power board all ok
no voltages on any of the boards outputs
Anyone had dealings with these power boards, or where do I start checking
I know I can get a used board off ebay however I would like to have a go at fixing this board myself, with your help of course

[ammarben]

Re: Samsung BN44-00194A power supply dead

first you have to check STD_5V delivred by VIPER22A
ICB801S and component around

[ammarben]

Re: Samsung BN44-00194A power supply dead

check for short diode DB401 SB560 and dont forget caps

[london-freddie]

Re: Samsung BN44-00194A power supply dead

DB401 seems to be ok no short, what where is SB560 can not find it

[ammarben]

Re: Samsung BN44-00194A power supply dead

DB401 is SB560

[london-freddie]

Re: Samsung BN44-00194A power supply dead

got that db401 is ok all caps look ok, 2 glass fuses in centre of board are good but no power at those fuses when power applied to board

[ammarben]

Re: Samsung BN44-00194A power supply dead

[sordids999]

Re: Samsung BN44-00194A power supply dead

https://www.badcaps.net/forum/showthread.php?t=46606

might help you along the way

[london-freddie]

Re: Samsung BN44-00194A power supply dead

no 5v

[sordids999]

Re: Samsung BN44-00194A power supply dead

checked for cold solder joints ?

[budm]

Re: Samsung BN44-00194A power supply dead

What DCV do you get between the cap CB801?
Notes: the SCHEMATIC may not be 100% correct.

[victor_cj]

Re: Samsung BN44-00194A power supply dead

Check or replace RB806, ZDB803. I had this zener diode faulty.

[london-freddie]

Re: Samsung BN44-00194A power supply dead

replaced power board with a used board tv powers up fine now, I call it fixed, however don't know what is wrong with original power board, thanks for the help guys

[budm]

Re: Samsung BN44-00194A power supply dead

Thanks for the follow-up.