Olevia lcd tv will not turn on.

There's a good chance you have failing electrolytic capacitors either in the power section or the inverter section or both.
Any caps in these sections that look bulged at the top, or bulged/leaking at the bottom (look for discoloration of the circuit board around the base of the capacitor) need to be replaced.
If you repeatedly turn it off and on, eventually it'll probably stay on, but every time you turn it off, the unit will get harder and harder to start up until one day it just won't.
Sometimes you have to do the opposite to start it up and unplug it for some time and then try again.

If you aren't tech savvy, don't worry, read the rest of this solution and watch the videos.

If you are handy with a soldering iron and can identify the power supply and/or inverter / FM section for the backlights, an inexpensive handful of capacitors will likely fix you right up.
Match the capacitance on the capacitors. Go over voltage if you can, and still have them fit.
IE - it's not a bad idea to replace a 10V cap with a 16V or 25V or even a 50V, but don't replace a 680uF cap with a 500uF or a 1000uF (unless you are SURE it's only doing supply output ripple filtering,
and even then, you should go OVER, not under the uF rating).

Most of the caps that go are 10V 1000uF or 3300uF.

I found some great videos of the procedure (for many Samsungs with the same issue) on youtube.

http://www.youtube.com/watch?v=Mm51C_RDIZE
http://www.youtube.com/watch?v=BNHHrgX_6cs&feature=related
http://www.youtube.com/watch?v=8l0AUj8QUkg&NR=1&feature=fvwp
http://www.youtube.com/watch?v=Y7b_nTaZYcU&feature=related

Backlight related video here:
http://www.youtube.com/watch?v=6XoF6QZ1dmw&feature=related

As you can see, this issue spans plasma TVs, as well as large and small LCD TVs and monitors, amplifiers, computer power supplies and motherboards, and other electronic equipment.
The parts are cheap, and skill required is minimal.
A great parts source is Digi-Key, and you can order the parts online at www.digikey.com
They typically cost under a dollar a piece plus a flat shipping rate.
The parts usually arrive one business day later.
If you watch the third video, you will see that even someone with no soldering experience can perform these repairs as demonstrated by the woman in the video.

my olevia a 232 s12 2nd hand tv . gift from a relative wont power on .just had the blue light on.i was able to reset my 32 inch olevia by pressing and holding down the power button much like a computer to reboot.might work for you.

I just repaired this identical problem on the same model TV. You have a bad power supply (also known as an SMPS). The board is model FSP271-4F02, and is about $75. Unlike the main board for this TV, you can find the power board relatively easily. Try shopjimmy, for example. Replacing the board isn't too difficult if you have a reasonable mechanical ability, have some tools, and are careful.

Well, at least the standby 5vdc circuit is still working but the problem can be in the controller board is not sending the signal to turn on the main power supply sections, or the power supply itself is bad. Look at the power supply first for burnt parts, bad capacitors.
http://en.wikipedia.org/wiki/Capacitor_plague

if it hot were you live t.v;s don't like heat above 35 degrees celsius

I have the exact same problem, haven't found a solution.

Finally recieved an email from syntax olevia customer support after 1 month. a standard desktop computer power cord is all you need for your Olevia LT26HVE flat screen. We lost ours in a move and FINALLY have it up and running again...for only 9 bucks at RadioShack!

>  I heard they were restructuring their company or something.
There has been a change ownership from Syntax-Brillian to Olevia International Group.
Details of Olevia brand  
Unfortunately for all of us (we have 747i) service seems very poor and the failure mode you describe doesn't give me any clues despite 40+ years of service experience.
Ours is still 100% but I now suspect our trouble will come.

since it's broken, proceeded to disassembled LT27HVX, re-seated connectors that go to the main circuit board that's in the middle of the tv, there are 3 (single row, about 15 or more pins) connectors, simply unplugged / plugged them several times to clean the contacts, must have been a bad connection somewhere, LT27HVX now works fine, only recommeded if you're technically inclined to open up the tv.

My 3 yr-old 30" Olevia LCD HDTV lost picture after being on for about 1-2 min. Does any one encounters a similar problem or has any suggestion as to how or wherther it can be fixed. Thanks.