Okay, I just wanted to make sure that I am looking at the right diagnosis per the blink code to give you an accurate answer.
The symptoms you have indicate a failing component in the TV. There are several things that could cause the issue, and I will try to explain them the best I can here.
First is the power supply, as there are several caps that become out of spec and can cause the TV to take longer and longer to power up. Average cost for this type of repair is around $250 parts and labor on this set.
The other is the Mainboard, which carries the communication needed for the supply to turn on and provide the voltages needed to operate. Average cost to replace the mainboard is $350 parts and labor.
Lastly, the sustain boards as they are the hardest working boards in the set and run very very hot. Failing sustain boards are very common in these sets, and typically run around $450 parts and labor.
The only way to isolate is to have a tech measure the voltages from the power supply, and also to check the sustain boards for shorts.
I'm sorry I don't have a quick fix for this problem, but it will require testing and components replacement to fix the TV.
If you'd like you can use the site below to locate a tech in your area:
If you need further assistance let me know and I will continue to assist.
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