Sometimes, you can tell if it's the foot control by having it plugged in, squeezing it so it's full throttle, then wiggling the cord. The cord is likely to have a break in the end where it connects to the machine or where it connects to the foot controller. You can usually find that break by wiggling the cord at both those locations while the foot control is squeezed. The machine may sputter to life off and on. The cord and little circuit board can be replaced. It is part #0094944.71.01 and is about $40. If you could get another foot control to try it out before you buy one, that might be a good idea.
It's not likely to be the power circuit board (L-Print), because the machine turns on. It could possibly be the Mother Board (s-Print), which retails for about $426. If that's what it needs, it's probably not worth fixing.
Last edited by quiltedsunshine; 08-15-2021 at 07:39 PM.