I was having an issue with the filament not loading. The filament would load all the way to the extruder then pull back. I replaced every part of the extruder, including all the boards and the problem still persisted.
I finally decided to take the AMS Hub off and look at that. When I unscrewed it, there was small rectangle magnet stuck to the side of the case. It took a bit to figure out where it came from, but I took the top board off and under there on the piece next to the spring there is a spot where the magnet goes in. It seems like it was glued it, but the glue failed…..I should have taken a picture.
I put it back together and everything is working.