LG TV Repair

[vidarr]

Hey guys, I want to resolder this pin back into the circuit, but want to know if there is a way to test the component it belongs to to see if it is still working. Or, should I just resolder the pin and turn it on?

The TV is old, so it is no major loss. But, if I can fix it, that would be great.

Thanks!

[wasedadoc]

That appears to be a transformer in a switch mode power supply.  Question is why has that pin become unsoldered?  If it got too hot because of excessive current, most probably the transformer itself is not the culprit.

[inse]

Mechanical and thermal stress…
Just resolder it

[vidarr]

OK, I will do it. Thank You for your input!

(Just FYI for others, I actually rolled back the solder away from the pin to get a better look at what happened. It was originally just a <0.5 mm gap around the pin. It appeared to just have melted away.)

Thanks Guys!

[TheMG]

If it was overcurrent the weakest part of the trace would go first, not the pad itself.

Likely solder joint cracked as a result of thermal stress and if this is in the high voltage side of the transformer the resultant arcing is what burned the pad away.

Solder it up and see what happens.

[vidarr]

I am on it. Will post the results tomorrow.

Thank You!

[vidarr]

Unfortunately, it did not work. But, now, I have a lot of parts.

It was worth a shot.

Thanks!

[slbender]

Hi, 

It looked to me like that pin may have intentionally been bent out of the way (last photo) and is not used - is  that a possibility?  Therefore, the fault lies elsewhere in the set.

Steven

[inse]

Maybe the arcing also killed the power semiconductor…

[vidarr]

Yeah, I think the component is fried. The TV is too old and not worth the time/money to buy new parts for, so I disassembled it and made a giant light table out of it for my daughter.

Thanks!