Unfortunately, the issues you are experiencing are symptomatic of an internal hardware defect, often a faulty power supply or main/control board, though there are many possible failure points. This issue could be a manufacturing defect, but is also often caused by a power event (shock/surge, prolonged over/under voltage condition, etc).
This could also be the result of age related wear and tear, as a 2004 model tv, that type of failure wouldn’t be surprising. Being able to get it to come on after many tries or repeated unplugs tends to implicate a bad/degraded power supply.
There is one step you can take here, both as a possible fix, as well as a diagnostic evaluation
1) Unplug the power cord from the tv
2) Wait at least 1 hour (60+ Minutes)
3) Press and hold the power button (on the set, not the remote) for 60 seconds
4) Keep holding power button while plugging back in, and for another 60 seconds after. When plugging back in, go directly to the wall outlet, bypassing any power strips or surge protectors.
If this reset process does not work, it would unfortunately confirm an internal hardware failure.
This is something that would require repairs to correct; if you're thinking about a do it yourself repair, you'll need to be comfortable and skilled with electronics repairs, which would require dismantling the set (removing the back panel of the tv), diagnostics with a digital multimeter to test voltages inside, changing out boards as needed, and possibly desoldering/removing and soldering/replacing capacitors (a common failure point).
If you’re considering repair at a local shop, you’ll find a typical repair to be around $300-500 for diagnostics, parts, and labor. However, parts are nearly impossible to come by anymore.
For a tv of this age/type (which is long discontinued and obsolete now), replacement will generally make more sense. You can get a brand new LED tv with a fresh warranty, better picture, and fresh warranty for not much more than repairs.
Depending how you’d like to proceed here, I can help with finding parts, finding a repair shop, or recommending replacement options. Just let me know.
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