LG 55UH7650-UA needs a capacitor!

[vinceroger69]

Re: LG 55UH7650-UA needs a capacitor!

I'm thinking it's either there to protect them from heat coming off surrounding components, or to pull heat off of themselves? I'm trying to decipher the color codes of those resistors but the middle stripe is confusing me. It clearly looks silver but according to the chart it can't be silver, but grey instead. Also I don't know what that little black component is under the goop by my finger. There is no writing on it 😒

The black thing is a inductor.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

What is the purpose of that paste on the blue cap? I know certain size caps need to be glued down but those blue caps don't fit that. Why is it actually there? Anyone know

I'm thinking it's either there to protect them from heat coming off surrounding components, or to pull heat off of themselves? I'm trying to decipher the color codes of those resistors but the middle stripe is confusing me. It clearly looks silver but according to the chart it can't be silver, but grey instead. Also I don't know what that little black component is under the goop by my finger. There is no writing on it 😒

[EazyBone]

Re: LG 55UH7650-UA needs a capacitor!

What is the purpose of that paste on the blue cap? I know certain size caps need to be glued down but those blue caps don't fit that. Why is it actually there? Anyone know

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

zoomed in on those 2 pink resistors, one looks like its gone out of shape.

Yes I seen that. It's lumpy and rough looking.

[slybunda]

Re: LG 55UH7650-UA needs a capacitor!

zoomed in on those 2 pink resistors, one looks like its gone out of shape.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

I replaced the bad cap last night but still no power. The surrounding components may be bad. Still need to get my multimeter to check those.

[lotas]

Re: LG 55UH7650-UA needs a capacitor!

Transistors don’t always burn out, sometimes you’re lucky and only the capacitor and fuse burn out. Check the resistance of these mosfets and the two diodes on the back of the board.

[alfatv]

Re: LG 55UH7650-UA needs a capacitor!

. Are you suspecting damage to those transistors as well?

Yes. The damage would be short circuit between 2nd and 3rd pin.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

Ok that's a good idea. I'll look at that other one. Are you suspecting damage to those transistors as well?

[alfatv]

Re: LG 55UH7650-UA needs a capacitor!

1kV is voltage rating, most likely you need that type, but you also need capacitance, somewhere around 220-470pF. Take a look at blue cap in 1st picture, very likely it's the same type. Also check both transistors mounted on a heatsink.

[x_orange90_x]

I got an LG 55UH7650-UA that I could hear popping when I plugged it in. After opening it up I found a ceramic disc cap that's completely obliterated. I can't find a schematic for the board, and the cap is obviously unreadable. I read someone else on another forum ask about the same cap, or so it appeared. Their board however looked different and the cap was in a different location on the board.

I have junk power boards with a bunch of these style caps, but most are 1kV or 250v. How can I be sure I get the right rated cap if I don't have a schematic?

The board in my TV is EAY64210702.