How long have you had the set for and when did the problem occur?
Was it after a storm or power outage?
Additionally, are there any click, buzz or hum sounds coming from the set?
So the set is only 6 months old correct?
Please disconnect the set from AC power for 2 minutes, then upon plugging back in, press and hold the power button for 8 seconds to try and force a reset.
If the TV still does not power up, then the flashing light would indicate that there is a short inside the set stopping it from fully powering up.
It is most probable that there is a failure on the power supply board inside the TV. Commonly the capacitors on this board will receive a surge and then fail. They can sometimes be visually verified by removing the rear of the set and inspecting them for bulges or leaking fluid at the top or the base of the caps. This is the most common mode of failure for these sets.
Seeing as you are barely into owning the set, you should contact the retailer and persistantly demand an exchange for another TV. If not, then you will need to ask them where the closest service location is to have the TV repaired. I wish I had better news, but there are no buttons you can press to fix this and the TV will require service at this stage.
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