What type of fuse is this?

[Malachi]

Re: What type of fuse is this?

There are two of them so remove them and test them off the board.

Remove the bridge rectifiers or the MOFSET's?

[budm]

Re: What type of fuse is this?

It is easier to remove the MOSFET's.

[Malachi]

Re: What type of fuse is this?

Took the MOSFET’s out of the board. The top one in the picture measures about 2.2M ohms. Keeps fluctuating.
The lower one reads 0.2 ohms.

On the board the bridge rectifiers are about 2.2M ohms.

[Malachi]

Re: What type of fuse is this?

Order the fets?

[tom66]

Re: What type of fuse is this?

Lower one is shorted but I would replace both and also look at the gate driver chip and consider replacing that too.

[Malachi]

Re: What type of fuse is this?

I already ordered both fet’s yesterday. Which is the gate driver?

[Malachi]

Re: What type of fuse is this?

Can anyone tell me which is the gate driver?

[jetadm123]

Re: What type of fuse is this?

From budm's photo in post #58, the gate driver is the black surface mount ic between the the two mosfets you checked. It's ICP801. I suggest you go ahead and replace it.

[Malachi]

Re: What type of fuse is this?

From budm's photo in post #58, the gate driver is the black surface mount ic between the the two mosfets you checked. It's ICP801. I suggest you go ahead and replace it.

Thanks, that looks to be above my skill level. If the two mosfet's don't fix it, I think I'm giving up on it.

[tom66]

Re: What type of fuse is this?

Worst case if the gate driver is bad the new MOSFETs will blow, about 75% of the time the driver ICs seem to survive.

[Malachi]

Re: What type of fuse is this?

Worst case if the gate driver is bad the new MOSFETs will blow, about 75% of the time the driver ICs seem to survive.

We shall see. eBay sells a kit for this psu with the fuse and the 2 mosfets. So must be a common fix.

[Malachi]

Re: What type of fuse is this?

The fets are arriving today, will update afterwards.
What is the white compound that is put on them? Not the thermal compound but the hard stuff? I had to cut it off. Do I need to put that back on afterwards? What purpose does it serve?

I also have thermal pads. Can I use that between the fets and the heat sink or is compound preferred?

[tom66]

Re: What type of fuse is this?

The hard, goopy stuff? That is used to hold the components in place during shipping or if the TV is moved. You do not need it.

[Malachi]

Re: What type of fuse is this?

Thanks Tom.

[Malachi]

Re: What type of fuse is this?

Good news. Replacing the 2 MOSFET's fixed the issue.
The bad news, see the attached picture.

[tom66]

Re: What type of fuse is this?

Bad panel. Sorry to see that.

It seems that these are really nice Samsung panels but very poor life.

Small chance that when power supply faulted it caused damage to address/data drivers -- but bad design if so.

[Malachi]

Re: What type of fuse is this?

Hopefully I can recoup my $40 dollar investment by selling the main board, power supply board

[JohnNovak]

Re: What type of fuse is this?

Usually, in case of failure, the lamp is used instead of the fuse during repair.
It save components and you have visual information about power consumption.
Light bulb is very good assistant during repair.

[tom66]

Re: What type of fuse is this?

Hopefully I can recoup my $40 dollar investment by selling the main board, power supply board

Everything works aside from the panel, so there's that. You can also have some fun with the plasma panel by removing the heatsinks from the address drivers and running it . They will begin to burn out and fill the screen with a rainbow of effects.

[Malachi]

Re: What type of fuse is this?

Well, coppeltv repair bought the psu for $50, so I’ve made my money back.