Ameens "lost post" is right. The "remove one wire" bit was before I saw for sure the motor had a plug. The goal was isolating the motor.
Isolating items for tests you can leave at least one connection in place. But two or more in place may lead in a circle thru other items, to the other leg(s) giving false reads (or in this case short out in the board before the motor can even try to use the power)
It depends on how things are connected. Some times it isn't needed, but you have to look and check.
Mostly it's just as easy to pull a leg or two off the board once the iron is warmed up.
And while on my mind, solder wont stick to stainless steel. So stainless tools are my preference. My best come from manicure kits. But the fishing box, the dentist and doc.s all contributed too 😁. Even SS tweezers work out well. Zircon encrusted is ok too. 😏 (it's not just for dental floss harvesting from your pygmy pony's saddle anymore 🙃)
