LG 55UH7650-UA needs a capacitor!

[lotas]

Re: LG 55UH7650-UA needs a capacitor!

At this point, this is not the best option, since mosfets and diodes have not been tested, it is better to use a 100W incandescent lamp instead of a fuse for testing; if the power supply works, then install a regular 5A fuse.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

Any serviceable, working fuse should show 0 Om on the multimeter; a faulty, non-working fuse will not show anything.

So the first thing I should do now is replace that fuse and see what happens? All I have on hand is the one I tested that was the correct fuse but also showed 1.000, and a couple 7.5A 250v. Would it not be a good idea to replace a 5A with a 7.5A?

[lotas]

Re: LG 55UH7650-UA needs a capacitor!

Any serviceable, working fuse should show 0 Om on the multimeter; a faulty, non-working fuse will not show anything.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

As I thought, it was this one that burned down?

Yep. The one with the red stripe. Question though, do 125v and 250v fuses have to be checked differently? I checked another suspected good 250v fuse and it also read 1.000, but when I checked a 125v it tested good. Meter is set to AC and Ohms (the only seeing I have).

[lotas]

Re: LG 55UH7650-UA needs a capacitor!

As I thought, it was this one that burned down?

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

I checked it and I get 1.000 both ways. My meter only has one ohms setting so that's what I used. The other fuse read good.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

You need to unplug (de-energize) the TV from the outlet, and then measure the resistance of the fuses.

I will recheck this later. Thanks.

[lotas]

Re: LG 55UH7650-UA needs a capacitor!

You need to unplug (de-energize) the TV from the outlet, and then measure the resistance of the fuses.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

When I set it to Ohms it bounced around all over the place. DigiKey's website recommends checking voltage for a fuse that's in-circuit. A working fuse should show 0v.

Is .28v an indicator that the fuse is bad? Or is that close enough to 0 that it's good?

[lotas]

Re: LG 55UH7650-UA needs a capacitor!

Fuses are checked for resistance with a multimeter; a working fuse should show a short circuit!

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

I checked the fuse. It's showing .28v with the power on. The other fuse on the board stays at 0v.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

How do you repair equipment (TVs) without a multimeter?

😆 I haven't needed to use it until recently. Last time I used it was just before my basement flooded, so I think it was misplaced after the cleanup. I have an idea now where it may be though.

[lotas]

Re: LG 55UH7650-UA needs a capacitor!

How do you repair equipment (TVs) without a multimeter?

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

Unfortunately I can't find my multimeter to test anything ��

What is more likey to be bad? The fuse, or the transistors? Or maybe all of them? I have some donor boards that may have the right transistors.

[diif]

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

It's being used as insulation.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

If it sparked, it means it was shorted, then this fuse could have burned out; you can simply check it with a multimeter.

I'll check that tonight. That would be great if that was the issue! So the fuse is further in the circuit than the cap that shorted?

[lotas]

Re: LG 55UH7650-UA needs a capacitor!

If it sparked, it means it was shorted, then this fuse could have burned out; you can simply check it with a multimeter.

[x_orange90_x]

Re: LG 55UH7650-UA needs a capacitor!

Have you checked the fuses?

No I haven't. They don't appear burned or anything, but they are the white ones, not glass, so the inside may be a different story. I imagine they are ok because the bad cap was still sparking before I replaced it. If the fuses were blown the power wouldn't make it over to that cap, right? Btw there are two fuses on this board.

[lotas]

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.

Have you checked the fuses?

[lotas]

Re: LG 55UH7650-UA needs a capacitor!

I 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. 😒

These resistors are wirewound, low resistance 0.15 Ohm 1%.