Don’t do this at home. Of course you should get a licensed electrician to do electrical repairs.
Make sure any electrical appliance you are working on is of course disconnected from any power supply. Some appliances can store electricity, so again I warn, do not do this at home, take your broken electrical appliances to an electrician – or do as I was tempted to do, just buy another drill. But this drill was given to me by my dad and it’s been through a LOT, and I wanted to see if I could fix it myself before resorting to another trip to Bunnings.
So first, I established that it just stopped, but would jump back to life when in certain positions. Classic short from a loose connection. Pull it apart and have a look, it’s not rocket science. I quickly found the broken wire, trimmed it up, stripped a fresh section of wire and re-attached, reasembled and Bob’s my uncle.