I don’t know much about electronics, but I’m curious. When a board like this (PSU for an LED tile) won’t supply power, what are generally the things to look at/for? I know I’m not showing the traces, so you’ll probably make fun of me, but I’m kind of just curious as to what is (statistically) most likely the problem since this seems to happen so frequently. Bad transformer?
>>994779
if it worked and then stopped, bad solder joints or capacitor shorted.
if it was it's maiden switch on and you fucked something up on the load side, fuse.
least likely are MOFSETs and control logic, but that doesn't mean they can't fail.
>>994787
>least likely are MOFSETs and control logic
Zapped MOSFETs are (or at least were some years ago) the single most likely problem in PC PSUs.
>>994833
Overheated semiconductors are still the leading cause of failures here. It's a SMPS and I don't see too many heat sinks here.
One if the biggest problems with getting electronics advice from this board is that you have neckbeards like >>994787 proclaiming that every problem you run across is bad solder joints or worn our aluminum capacitors which, in fact, are two of the least likely problems you will ever run across. It's like, just because some other 4chaner told them once that those could be problems, now they have to go around repeating that like a parrot. It reveals how little experience they have, but the first timers here get inundated with that response and start to believe it too, further propagating the myth.
The next thing you know, you have a beginner who just destroyed his project with a soldering iron when all they had to do was change a fuse or turn on the power strip that it was plugged in to. /diy/ just ain't what it used to be.
>>994840
/diy/ used to be incredibly helpful and encouraging. I mean they still told people to kill themselves, but not every thread devolved into a bunch of anons arguing over how much of a retard the OP was for not being a tradesman/electronics expert.
>>994820
>>994840
Bad caps are pretty common on the low end. I've repaired a monitor psu on a notorious line that had bap caps, and for almost a decade computer hardware was rife with them: https://en.wikipedia.org/wiki/Capacitor_plague Reportedly one of the later cases was due to a guy stealing a Japanese design incorrectly.
My first-gen 2560x1440 monitor died, and it either contributed to the exploded caps, or was caused by it.
Also, I haven't seen a single switched mode supply that didn't have huge heatsinks going across the board, albeit no airholes.
Only once have I ran into an electronic device certainly failed from not capacitors, and that was the head of a Dyson vacuum with a possibly underrated resistor.
>>994779
Look for where the magic smoke came out. Replace those components first. There will be a hole and some black marks. If you can't find them, look harder. Then you can start troubleshooting other things.
>>994840
shitty transformers. that's basically it. oh how i wish my problems could be solved by recapping when it's 9/10 times I would rather throw the whole piece of garbage away than rewind a transformer
>>994779
I actually have seen this quite a bit on LED power supplies. The primary side transistors fail due to thermal issues. Mine had a blown capacitor as well - adding a heatsink to the replacement did the trick for me.
>>994820
that light bulb
