Samsung PS64e550 psu replacement

[magoo]

I've purchased a new replacement PSU board for my lifeless PS64e550, however while it now powers on briefly it then switches back off after a couple of minutes. Would anyone have some suggestions on the further diagnosis I should do to work out what other board may need replacement or if I need to adjust some voltages , I understand repairing a power failure may not be as easy as swapping a faulty board.

The symptoms I've seen since replacing the psu with a new one:
- initial red sparkles on the first boot
- an electrical noise coming from the new psu
- tv then power cycles and attempts to start again.

I'm leaning to buying a used replacement y-main board, but don't want to purchase a board on a hunch only to find I have to replace several others as well or wasn't the cause. If anyone knows the next steps a technician would take to isolate the cause of the restarts, or if there's a known post process of replacing a Samsung power board I'd greatly appreciate it.

Thanks in advance.

[tom66]

Re: Samsung PS64e550 psu replacement

So, a question, when the TV briefly powers on, does it "work" at all, e.g. a proper picture, and then shutdown... or... is something else happening?

[magoo]

Re: Samsung PS64e550 psu replacement

I actually hadn't verified that as don't have the channels tuned and switches off too quickly to test, but system menus appear correctly. It previously had no display issues prior to the power failure.

[magoo]

Re: Samsung PS64e550 psu replacement

I've checked and the picture displays fine before rebooting, is there some voltages I may need to adjust, I've also read buying a second hand Y main board might not work as needs to be reprogrammed? Would this be likely?

Thanks again

[magoo]

Re: Samsung PS64e550 psu replacement

Does anyone have any input they can provide on this?

[tom66]

Re: Samsung PS64e550 psu replacement

Have you tried to engage the test pattern generator on the logic/control board?

[magoo]

Re: Samsung PS64e550 psu replacement

Apologies for my ignorance, I'm not sure how to do that. It would likely shut down within 60 seconds and may not have the opportunity.

[PowerAmpFreak]

Re: Samsung PS64e550 psu replacement

Did you trim VA and VS according to sticker on panel?

[tom66]

Re: Samsung PS64e550 psu replacement

Apologies for my ignorance, I'm not sure how to do that. It would likely shut down within 60 seconds and may not have the opportunity.

https://www.badcaps.net/forum/showthread.php?t=26790

[magoo]

Re: Samsung PS64e550 psu replacement

Did you trim VA and VS according to sticker on panel?

I believe this could be my problem, after buying another YSUS board the sparkles appear once more and now reboots after around 5 minutes.

Would I need to adjust the VS on the power board or the YSUS board as I've noticed there is a pot on it as well as the two on the power board.

Thanks for the suggestion.