Samsung ue40d6510 no sound black screen

[Cryogen]

Power supply tested and working.

Motherboard I am quite sure it works as when I push the menu button backlight gets brighter.

I have removed the tcon board and sound a short on a tantalum capacitor.

Can anyone tell me if the capacitor is gone or the transistor is the culprit?

Thanks.

[budm]

Re: Samsung ue40d6510 no sound black screen

Start with this:
https://www.badcaps.net/forum/showthread.php?t=39740

[Cryogen]

Re: Samsung ue40d6510 no sound black screen

Start with this:
https://www.badcaps.net/forum/showthread.php?t=39740

Thanks, but I am quite sure it is the tcon. The tantalum cap in the picture is shorted. I have tested the transistors and they look fine.

[budm]

Re: Samsung ue40d6510 no sound black screen

So the SMD 5A fuse is blown and replaced with jumper wire? If the fuse was blown, then yes, you do have problem on the T-CON board.
Remove the suspected bad part and measure the parts off the board to see it they still show as shorted circuit.
BTW, those 3 caps look to be connected in parallel, so check the pads on the board after the caps are removed to see if it will show low resistance.

[Cryogen]

Re: Samsung ue40d6510 no sound black screen

The smd 5a fuse where? On the tcon? Aye I have jumper wired it.

Low resistance? Do you suspect trace damage?

[Cryogen]

Re: Samsung ue40d6510 no sound black screen

Do you think the transistor might be faulty? Usually a tantalum shorts when there is a bad transistor.

[budm]

Re: Samsung ue40d6510 no sound black screen

Tantalum usually failed short by itself.
BTW, which transistor? Why don't you just remove the caps?

[Cryogen]

Re: Samsung ue40d6510 no sound black screen

Tantalum usually failed short by itself.
BTW, which transistor? Why don't you just remove the caps?

I am going to desolder the cap and let you know.

[Cryogen]

Re: Samsung ue40d6510 no sound black screen

I have removed the cap and it is completely dead. I also noticed a short between the board pads as you suggested.

What am I gonna do with that?

[budm]

Re: Samsung ue40d6510 no sound black screen

So the removed caps tested as shorts and also the the resistance between the two pads for the caps also shows as shorts? If that is the case, you have more work to do to trace out the circuits.

[Cryogen]

Re: Samsung ue40d6510 no sound black screen

So the removed caps tested as shorts and also the the resistance between the two pads for the caps also shows as shorts? If that is the case, you have more work to do to trace out the circuits.

I have measured the transistor showed on picture. It gives a short on on of the two pads. I suspected this since the beginning. Transistor always short other components.

What do you think?

[budm]

Re: Samsung ue40d6510 no sound black screen

Always remove the suspected bad part and make the test off the board.
BTW, the silkscreen shows it as IC50xx so that does not look to be Transistor, the silkscreen for Transistor on that board is shown as Qxx.
Are the traces from the caps connected to that IC directly?

[Cryogen]

Re: Samsung ue40d6510 no sound black screen

Always remove the suspected bad part and make the test off the board.
BTW, the silkscreen shows it as IC50xx so that does not look to be Transistor, the silkscreen for Transistor on that board is shown as Qxx.
Are the traces from the caps connected to that IC directly?

Aye, it looks like they are on the same trace.