My Janome Memory Craft 3600 is locking up and it seems like the main shaft is freezing. Can it be fixed to stop locking up?

If these two don't carry it, or can't order it, no one can

Janome Memory Craft 7000 Parts and Accessories

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The Janome Memory Craft 7000 parts and accessories on this page are guaranteed to fit the Janome Memory Craft 7000 sewing machine or your money back.

Janome Memory Craft 7000 Sewing Machine Parts

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Shop our extensive selection of Janome sewing machine and serger parts and accessories! Quick delivery. Free shipping over $49. Easy 90-day returns.

Bag with handle

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What do your paper or on-line manuals say about BM init errors, please?

can you not take or send the machine back, you say you just bought it?

Balancing Thread Tension - Janome MEMORY CRAFT ...

www.manualslib.com > ... > MEMORY CRAFT 4900 QC > User manual
Janome MEMORY CRAFT 4900 QC Manual Online: Balancing Thread ... Auto-threadtension When the thread tension dial is set at AUTO for ... to increase the threadtension. ... Sewing Machine Janome Memory Craft 350e Instruction Book.

The Janome Memory Craft 11000 does indeed have fuses on the main circuit board. Often, if one of the motors becomes overloaded, as is occasionally the case if thread gets bound up in the hook/bobbin area, it will blow one of the fuses, to prevent serious damage to the motors or mechanical parts.
They are not easily removed at home, and doing so would not be advised as you would be dealing with delicate electronics on a very expensive machine. I would recommend taking your machine to a Janome dealer to have it fixed. There are a few other possible problems, thought the fuse is most common, and it would be better to have it diagnosed by a technician.

then it needs to be fixed by a sewing machine shop

Your machine is a "computer" and needs a qualified Janome repair tech.

Try this link for an affordable solution to repairing your Janome MC 5700 Display Back Light.

https://sew-bright.com/products/janome-memory-craft-5700-lcd-backlight-replacement-kit

I have a memory craft 8000 that gets a message stating "Stepping Motor Error". What can I do to try to fix it?