My 53WUX10BA Red Power light will not go out

These blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices. http://electronicshelponline.blogspot.com/
Blinking codes details to many popular brand TVs are given. Surf the site with patience.

Make sure the cord is pushed in all the way on the back of the tv. If it is then check for fuses on the power supply board inside the tv

check the fuses

Could be try putting your power LED on your HDD LED header on your mainboard and then look at this while booting up and this will tell you if its the LED or the Header on your mainboard

I had this on mine too. It is a problem with the power supply. Samsung knows about it.

With KG02 removed, the short lies in B+ 115 V1.

just one idea.. some set you may program to stay on in case you use cable box and when you turn on the box tv turn on same time but may be defective tv there is relay,transistor and the micro that may be bad so check your settings again ... Good luck

If your talking about the little red LED on the front of the set don`t concern yourself over it, you have a diode that is a little "leaky" which just means it`s partially on when it`s supposed to be off. The diode is a pain to get at to replace it and it will NOT hurt your set to just leave it like this.

You can download a PDF from here: http://www.servicemanuals.net/results.aspx?type=SM&brand=0&model=50EX20B Make sure that the coolant is not leaking out onto the printed circuit boards. i have had the remote sensor cause this problem before and also I have had bad capacitors in the sweep and the main power supplies. Good Luck

Yeppers. Sounds like the standby power supply has a bad capacitor in it and the regulator Ic is defective. These parts should only be replaced by quilified technician as there is very high voltage inside these sets. Good Luck