Motor Control Board Fried!

[Marky_Mark]

Hi guys


I'm having an problem where the motor doesn't run at all. I’ve already tried replacing the capacitor and even swapped in a new motor, but neither made a difference.


Upon inspecting the control board, I've just noticed what looks like a burned spot. I’ve never soldered anything before, but I’m willing to invest in the tools and learn how to do it properly.


Is it possible this could be fixed just by re-soldering that joint?


Appreciate any advice—especially from the electronics pros here, like @phillymatt53. Thanks in advance, Mark.

 

[Unimatic1140]

Hi Mark, I guess the first thing I would do, if you have an electrical multimeter, is check to see if there is continuity (zero ohms) between the burned point and the other three points that it connects to.

 

[Marky_Mark]

Thanks, Robert. I do have a multimeter and I'll go and check that now.

 

[Marky_Mark]

Actually, I'm not seeing any continuity anywhere on the board at all, so I don't know what I'm doing wrong. It's as though the solder isn't conductive at all! My multimeter does show continuity when I touch the leads together or test something else.

 

[phillymatt53]

Actually, I'm not seeing any continuity anywhere on the board at all, so I don't know what I'm doing wrong. It's as though the solder isn't conductive at all! My multimeter does show continuity when I touch the leads together or test something else.

Mark, that board's got Muliple Issues from what I can see.
It appears to be a relay board, am I right?
If you look Closely at all the soldering connections, there are plenty of cracked/loose connections, particularly on those connector plugs.
With a magnifying glass, you'll see circular cracking of the solder around the connector pins, among other bad joints around that board.

While the photo isn't clear enough, I've managed to point out the most obvious bad joints - However, if I were working on that board, I'd go over EVERY solder joint on the board, regardless if it looks fine, and all 3 connectors.
It's got poor soldering and black arcing of some questionable connections.
Make sure you do not bridge closely arranged connections with solder!
A 40W soldering iron and some lead-tin solder should result in a working relay board, IF it hasn't caused other damage to the connected board used with it.

This is what likely causes these "modern" electronic machines to break down.
And it's why I refuse to ever own one.

 

[Marky_Mark]

Hi Matt! Thank you very much for taking the time to do that -- I really appreciate it!

Yes, it's a relay board. Thanks for pointing out the other dubious parts, which I had noticed looked "different" but I didn't know if it was a problem. I'll get a 40 W soldering iron and do my best to fix it. I'll practice on something else first! I'd like to keep this machine if I can.

Mark

 

[phillymatt53]

Hi Matt! Thank you very much for taking the time to do that -- I really appreciate it!

Yes, it's a relay board. Thanks for pointing out the other dubious parts, which I had noticed looked "different" but I didn't know if it was a problem. I'll get a 40 W soldering iron and do my best to fix it. I'll practice on something else first! I'd like to keep this machine if I can.

Mark

Good luck, sorry I can't offer any guarentees if it doesn't fix the problem.
Because I do my best troubleshooting on my workbench, impossible through the internet.

 

[Marky_Mark]

Thanks, Matt. I'll be sure to post an update! I've been meaning to get a soldering iron, as my husband has a small portable fan that I want to fix for him (USB power connection has broken off).

 

[phillymatt53]

Thanks, Matt. I'll be sure to post an update! I've been meaning to get a soldering iron, as my husband has a small portable fan that I want to fix for him (USB power connection has broken off).

Make sure it's a pencil-point tipped iron.
Use rosin core tin-lead electronic solder only.
And don't forget to unplug that washer before anything!
Carefully scrape any blackened areas to allow the solder to adhere better.
Minimize any unneeded flexing of the connector wiring.
And double check for any splashes of solder that may happen.
Slow, careful, patience.
Those relay connectors/wiring have to handle the main power - heavy current.

 

[Marky_Mark]

Thanks so much for those tips, Matt.

"Carefully scrape any blackened areas to allow the solder to adhere better."
Thanks for letting me know. I was going to ask what kind of prep, if any, I should do to those blackened areas.

I've ordered these things, among other helpful bits and pieces. Notice the fun little kit for learning to solder!

 

[phillymatt53]

Thanks so much for those tips, Matt.

"Carefully scrape any blackened areas to allow the solder to adhere better."
Thanks for letting me know. I was going to ask what kind of prep, if any, I should do to those blackened areas.

I've ordered these things, among other helpful bits and pieces. Notice the fun little kit for learning to solder!

That soldering paste won't be needed, because the solder already has a rosin core built into it.
Practice makes perfect!
And DO let us know how things work out.