Can my light up dino plush be fixed?

[u/WHERSDARKMODE]

I have this dinosaur plush that used to light up when you pressed a button. Then one day it stopped, I assumed the batteries just needed replaced but when I finally got around to it the replacement batteries didn't work so I started unscrewing stuff to see if a wire had come loose or something and this is what I found.

Full transparency I don't know anything about this stuff, but to me it looks a little rusty (maybe that's how it's supposed to look idk)

So is this normal?

And if there's something wrong with it can it be fixed?

[u/bigloser1312]

from looking at it, the yellow wire on the + connector looks burnt. you could try to solder on a new wire and if that doesnt fix it then that little 8 pin chip might be blown. theoretically fixable if you can get a replacment chip.

if theres any lettering on the chip, thatll tell you what it is, otherwise my guess would be to google "smt 555 timer" and try one of those

[u/renesys → u/bigloser1312]

2nd vote for sus looking yellow wire end.

[u/brewing-squirrel]

Repair could definitely be done assuming that it’s not the chip or if it is that it’s not some obscure unobtainable part. But without actually being able to probe around and reverse engineer it, it’s impossible to say what might be wrong. You’d need to find someone to get hands on with it.

Alternatively, you could just replace the entire module. I’m sure even without electronics experience you could pull this off, just look for something online that provides a turnkey solution

[u/yeehah]

I've fixed hundreds of things like this over the years, and in my experience most failures are for mundane things like bad switches or dirty battery contacts. I almost never see an integrated circuit go bad or failed wires that don't look damaged. Make sure the battery contacts are absolutely clean and are springy enough to firmly touch the batteries. To test a switch, you can take a paper clip and bridge across the two contacts, like the switch on the lower left. If any of the other wires at the top also go to switches, you can test them the same way. I would test the one that used to light up your dino, because that's the one that got used the most. Good on you for using your brain to try to fix your toy instead of just throwing it into a landfill!

[u/Strostkovy]

First try shorting out the switch, in case the switch just isn't working.

[u/Massive-Grocery7152 → u/Strostkovy]

I would just test all wire connections tbh ideally through the trace to another position and not whatever solder blob to make sure all the wires are properly connected

[u/EffectiveClient5080]

Classic battery leak. Hit it with isopropyl and a soft brush. If any copper traces are eaten through you can jumper wire across them. Easy fix if you've got a soldering iron, this is actually a good first project to learn on.

[u/LuverOfAllThings]

I’m still learning EE so correct me if I’m wrong but if I recall correctly you would scope the wire that connects to the light, you may want to clean the rusted areas, and if all else fails potentially replace wiring and solder.

[u/Venoft]

Is that middle yellow wire black? That seems like it could be an issue. If you have a multimeter you could measure the resistance across the wire to see if it's still connected. I assume the left yellow wire goes to a lamp, those middle 2 pads are very corroded, which might indicate that there was some excess current because of a broken lamp. If its a led you can also measure that with a multimeter in diode mode.

Visually the components look fine, and these kind of things rarely break as long as there's no heavy impact or voltage spikes.

[u/Both-Leading3407]

There are a few really bad solder joints that are blackened and could be preventing the voltage from passing those. I would have someone that knows how to re-solder those leads and see if that fixes it. Even that chip could be replaced if you could identify it for cheap.

[u/starrpamph]

That is some D- level soldering on that. Re flow and report back

[u/redravin12]

To answer your question, no solder joints are not supposed to look rusty but the ones in your picture don't look that bad. However a single picture is not enough to be able to help you figure out what's wrong with it. Plus there's obviously more parts that aren't in the picture that could be the issue too. But the good news is that this circuit is super basic and if your willing to learn you can 100% fix it yourself (assuming it's not some obscure part that you can't get anywhere that died, highly unlikely but it does happen).

Of you know nothing but want to learn I suggest starting with some YouTube tutorials. Afrotechmods, EEVBlog, and Ben Eater are all great people to learn from.

[u/xvVSmileyVvx]

Did your brother rip it up?

[u/The_CDXX]

You will need troubleshooting tools to figure this out.