Does this varistor look "blown"?

While watching, the screen went almost black—just a faint, gray glow. (I think the sound continued). I turned the TV off, then back on, and it worked for a few minutes before going dark again. I let it rest a few hours, then it worked again for a few minutes before emitting a whistle/buzzing sound (like a July 4th rocket) that went from a high pitch to a low pitch over about 5 seconds—then it turned off completely.

Now, when I touch the on button, the dim red light pulses 3 times, then goes off and the screen glows a very dim gray.

All of the cylindrical capacitors look very clean. Nothing oozing out of them, no bulging, etc. However, there’s a funny-looking green part (about 1/2 inch diameter and 1/8 inch thick— I’ve been told it’s a “varistor”) that’s green on the sides, with a bubbly, yellowish area in the middle. It’s a little sticky on the outside, like something’s leaked. The bubbles inside the clear, yellow area make me think this is the part that made the noise as it “cooked.”

Digit-Key support offered a part, based on the "TVR 14621 820W" printed on the outside:

It looks quite different, but great if it works, and would only cost about $5, including shipping.

Should I give it a try?

From the markings that I looked up for the 14621, the Littlefuse part number V385LA20AP or the Digi-Key part number F1955-ND should work

@rbanks88 It could be blown or be extremely corroded. I’ve never seen a TVS fail like this, usually when parts fail, they burst open/crack, but it’s very possible it’s blown from a technical standpoint.

It may be blown, and since these usually fail near-shorted it is best to replace it.

Thank you all for your input! I’ve ordered the part.


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