My orbital sander (Parkside PAEXS 20-Li B2) stopped working without any signs of an electrical short or a mechanical malfunction. Here’s how I got it working again, by simply spraying a bit of contact cleaner directly into the power switch, which had gotten clogged up with small dust particles.

I realize that in this case, it was an easy fix. Chances are — given that the switch is unsealed — for most of these orbital sanders that stop working for no apparent reason, that the switch is at fault, and it may only require a bit of judicious use of contact cleaner spray.

As I said in the video, the problem will re-occur, exactly because the switch is unsealed. It did for me, just a day after the fix. What I ended up doing afterward was to remove the sliding switch which sits on top of the regular, unsealed switch and now, with the real switch exposed, I can continue to spray contact cleaner directly into it, every time it gets clogged. It’s simple and it’s practical and it saves me from having to source a sealed switch of the exact same dimensions and solder it onto the contacts, which would take extra time and effort.

Hope this helps!