Does this actually happen? ... a coil is nothing more than a solid wire wrapped X number of times around a spool; without the entire coil melting into a blob of copper, it's actually physically impossible for the inner coil winding to contact the outer winding.

That being said ... the magnet board is designed in such a way that the resistor will draw close to 8 watts of power if the mangnet windings are open or the connection between the magnet board and magnet is broken. The original REV A magnet board had a 10W magnet board resistor that wouldn't burn under these circumstances but for some reason Stern changed this (I assume for cost) to a 5W resistor; however, the original 10W connection is still in place as well as the 10W resistor silk screen on the top side.

How do I know all this?

This happened to me as well.

DSC00317b (resized).jpg

My replacement board from Stern now has the appropriate 10W resistor installed as I modified this before installing the board. Please note that this resistor is also elevated off the board so that in the rare event it burns, it cannot take the board with it.

DSC00690 (resized).JPG

They do:

https://www.mouser.com/ProductDetail/603-SQP10AJB-160R

I'm glad you mentioned this as I just lost another board, this one is an odd failure though as all I have to do is power cycle the machine and it starts working again, but fails after a couple of locks. I'm starting to suspect that there is an issue with either the +5V power or the communications with the driver board. I may have to swap in my driver from Star trek and see if it fixes it.