I couldn’t find a whole lot of information on this. My HDTV (a Magnavox 37MF331D) had developed the nasty problem of not turning on when the power button was pushed. The power LED would flash green for a while and then go back off. I had to try turning it on several times before it would finally come on. This seems to be a common problem affecting a lot of HDTVs; it’s not even a brand-specific problem.
After much research, I determined that my problem was blown capacitors on the power board. By repeatedly turning it on, they gradually got warm enough to hold a sufficient charge to let the TV turn on. There still wasn’t much information about how to actually fix the problem, aside from a couple of YouTube videos that show you approximately where the affected board is inside the unit. So, I figured I would share what I learned. There are 4 capacitors that should be replaced (two of mine were showing damage but since they’re all the same brand it’s probably good to change them all out). I guess TV companies just like to spring for the cheapest components they can find. There’s also a larger capacitor further down the board, but that usually doesn’t need to be replaced.
This is what my blown caps looked like
and this is the nice new ones ready to not explode.
I got Nichicon for the smaller ones; I don’t remember what the larger one is but hopefully it’s long-lasting as well.
You need one 1200µf 35v, one 2200µf 25v, and two 1000µf 35v caps, all should be high temp (125°C). And of course, you can use higher-voltage caps if necessary. Try to get a good brand and not something gross like CapXon. Whoever they are.