I have to say that it is my honest opinion, not to replace this part.
Check the wiring carefully.
If thats not the problem, I would invest the money in a new machine.
The machine would be considered coming to the end of its life it was only used twice a week, but if you use it everyday at least once...........................!
The problem with spending such a large amount of money on an older machine is that next week you could have a relatively small part fail, that is no longer available, thus rendering the machine useless.
Im sorry its not good news, and you must do as you see fit, but I have to be honest with you, as I am sure you understand.
If I can help further, please just ask.
In the meantime,
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