@assaultpotato Thanks for your reply!

I haven't cycled with snow that much because I got a front wheel engine and it's got too much power to control in those conditions. But I have definitely dealt with gunk! It is just so strange that it is only *that* connector. It may be a "feck you in particular" kind of situation.

After fitting the rubber seal, the battery works again, but seeing the state of that connector, I'm worried the shaking will cause more damage.

@fubarx It is very odd. The shop that changed the battery cells told me the pins needed some cleaning "particularly one side", and they cleaned them themselves. Then weird connection and acceleration issues started happening, but on their website they warn this can occur sometimes.

Anyway. Sorry for the rant. The plastic is perfectly fine and so is the controller the connector fits in (or at least, I believe it is with the training I have). Haven't fully opened it, though.

Have been wanting to learn soldering for months so I believe I now have the best excuse possible.

@JayleneSlide Time to get some education! Thanks for the tips.

I looked at the controller's pins and they seem fine, but I'll clean them just in case.

I honestly think the shop that changed the cells did a shoddy job and I'm now paying the price. I found out three of the pins to close the battery are completely broken, so hopefully this doesn't mean the inside got corrosion too.

@JayleneSlide I am a DIY kind of person, but have never dabbled in soldering or electronics.

I checked iFixit as soon as the issue started but couldn't find anything helpful. German is rusty (nonexistent) though.

I'll have a look at Grin Technologies. Thanks!