I have a 50in vizio hdtv20a and the amber light is on in the corner but it will not power up

The number one reason for this is failed YSUS board EAX37106201 . There are two ICs on it and one of them shorts, preventing the TV to power on.

The second most common reason is failed power board EAY32929001. There are several different things that can happen on it, but the first I'd look for if I were you is visually swollen electrolytic capacitors on the board. Look that up on Google and you'll see plenty of pictures of what to expect.

The third reason would be a bad ZSUS board EAX34042701 / EBR37284601 . Same as with the YSUS, only this is less common and, this one can actually be tested really easy by disconnecting the ZSUS from power and trying to power on the TV again. If it does come on (even with blank screen) then it's the ZSUS that is bad.

You can and should do the same with the YSUS, but it will only work if the ZSUS gets power directly from the power board and NOT through the YSUS board. I am not sure how they were on P50HDTV20A in particular, but in those models usually the ZSUS gets power through the YSUS and thus if you disconnect YSUS from power you automatically disconnect ZSUS as well, which is not good for tests as the power board needs load on the Vs line.

Well...hope that helped...don't forget to rate it if it did!

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