Power outage in town; now my 50'' samsung serial # PN50B400P3DXZA won't turn off unless unplugged plus no button on the tv will make it do anything. in the top left corner it seems to be scanning through channels. when plugged in red light flashes every 1/2 second, continuosly

SOURCE: Samsung flat screen wont turn on red light just flashes..

wont turn on red light just flashes?
On my samsung flat screen tv when you are watching the televison there is no red light on the power button but when you turn the television off the red light stays on all the time? what can I do to turn this light off?

SOURCE: Samsung LNR408DX/XAA Wont power up

I had the same problem with a 52" Samsung LCD. I found 2 electrolytic caps with bulging tops on the power supply board. (see pic). I looked to be the 5v section but I'm not sure. I got replacement at Fry's for $1.90 each. All is well!
Ahwatukee Al

SOURCE: Bottom half of the screen is black on Samsung HP-R5072 50 in. HDTV Plasma Television

I have a solution. My Samsung plasma had the same problem with the bottom half of the screen being black. Follow these directions and it will not cost you a dime, just some time. I took the back panel of the tv. I found the lower buffer board on the left hand side. I disconnect all the ribbon cables. Use an air cleaner to spray out any dust on the ribbon connection and the board. I connect the ribbons back to the board. My plasma is now as good as new. If you have issue with the top portion, do the same with the upper buffer board. I was going to buy a new tv but I'm glad I gave this a shot first. It's been almost a month and it's still working fine. Hope this helps and hope it saves you some money.

SOURCE: Samsung 32" can not turn on

It could be a faulty power supply (capacitors). To all who are having power supply issues: Samsung is now acknowledging a problem with faulty capacitors. I called 1 800 726-7864 and they said they would repair certain out-of-warranty TVs if the problem is related to the capacitors. I just called and they are sending a service rep out to diagnose the problem

SOURCE: i have a samsung hp

When the power was restored you suffered a power surge. Anything plugged in that did not have a surge protector was at risk. plasma tv's are especially susceptible to this. You will have to take this in to a tv repair shop for an estimate.
If the estimate is over 200 you may want to consider a replacement. Also purchase a surge protector so this doesn't happen again. Regards, Joe