Red power indicator flashes six times

Http://service.us.panasonic.com/OPERMANPDF/PT53TW54.PDF
With this symptom, it is impossible to tell what the exact "Cause" of this symptom is. The LED's do not tell us what is wrong, sometimes it may indicate the "Area" in your case it is the X board. BUT thats NOT where the "Fault is" thats just the part that is affected. These days unlike the "Old" analogue days it just isn't realistically possible to fix anything but the most basic of problems with todays sophisticated units. This is quite apart from the Safety aspect, any unit that can cause a firs or have an explosion, or both, is NOT to be treated lightly, and and the repairer, of the unit is legally responsible, another thing to think about. Also, one must have tools, a Multimeter, a soldering iron, a deslodering iron, an oscilloscope, a signal tracer, tools, and most important of all, a Service Manual, without which, there is no way to even begin to understand and fix it, and more importantly Program it, AFTER it has been fixed. As these days a TV, is a PC, a Tuner, and an HDTV Monitor, and more, all in one. So, it is nearly always my professional opinion that one should always get a "Quote" form the manufacturers recommended service center, I cannot stress how important that last point is. It is even worth the cost of shipping. you see an authorised service agent, will have trained staff, trained on their brand, also they have first hand access to parts, original parts. This will actually save you money and ensure you can actually get it back fixed. Of course asking for a "Quote" also gives on the option of repair or replace. Often my clients,do not go through with repair, unless it is moderate, but in some of the more costly jobs they see it, as do i, that a replacement, with a warranty, is a better option. As an aside here, one could then tear the TV down, and sell the Known Good bits. You'd be surprised who needs parts, i myself often must by from third party sources to effect a repair. So money could be recouped, somewhat,and help out someone else. Anyway thats my 10c worth.