Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
What damage was there to the Main Logic Board in the TV, originally?
I cannot claim to be fully acquainted with plasma TVs made by Pioneer. However, no other Expert has stepped up to take on this question, so I feel I should offer what I do know.
The only info I can find on our 14 blink code is, in a Sony TV, it can mean 'panel failure'.
If that applies also to your Pioneer, that is a very expensive item to replace, and replacing the whole TV might be more economical.
But, that's uncertain to be relevant. I think you should get a service manual for this TV. It may save you more than its cost, in parts swapped in and found not to be the problem nor the solution... and also, it might well tell us what the 14 blinks means.
Would you be interested in a source for a service manual for this TV? if so, let me know.
If so, this appears to be a free-of-charge source, though the PDF blinks rather alarmingly: