samsung PS42B450B

[sordids999]

Ok got this tv today totally dead found the fuse bottom left on the psu had blown changed it and had a popping noise round that area when I tried to turn the tv on

Any ideas

[sordids999]

Re: samsung PS42B450B

By the way if you look at the heat sink it seems there has been some sort of arcing it's inside also on the back cover

[tom66]

Re: samsung PS42B450B

Fuse popping - check bridge rectifier, MOSFETs on heatsink, etc.
I -may- have a compatible PSU for this but it is for a slightly different panel (still B450 though, I think Samsung changed design half way through)

[sordids999]

Re: samsung PS42B450B

The psu is BN44-00273B LJ44-00171B

[tom66]

Re: samsung PS42B450B

schematic


Try removing other fuse on PSU and just leaving main one on.
Also do you have a bulb tester/lamp tester jig for testing PSUs built yet?

...Wait, is the fuse actually blowing or not?

[sordids999]

Re: samsung PS42B450B

Hi tom yes I got one made at work but it's still there and it blew the trip switch in the house but the fuses in the psu are still ok

[sordids999]

Re: samsung PS42B450B

hi tom i have checked the bridge rectifier thats shorted im in the process of trying to find a replacement board anyway thanks

[sordids999]

Re: samsung PS42B450B

Update:
Tested bridge rectifier which was shorted luckily had another on a previous board tv working at the moment so testing at the present moment......