Brother PR-600...does anyone know if it's a major problem if it says "main motor lock"? The needle broke while sewing, and it is stuck in the down position and will only say "main motor lock" on the screen?? Thanks for any info!

Perhaps you can find it here:

Brother 1034D parts diagram Google Search

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just adjust to needle in fix to strait in needle clamp hole it operate to needle strait to hole so needle do nt break but needle is best buy qualtity

Looks like the machine is bound up, or the motor is failing. If the hand wheel is easy to turn then it is probably the motor drawing too much current.
Brother recommends a new motor and belt every 1500 hours of run time.

The broken needle may be lodged in the bobbin housing. If you cannot locate, take it in for professional servicing. You may have put the timing out of whack.

You might have Thread particles build up. Puchase canned Air for electronis and use it on a regular basic to clean your bobbin case area. Also when you change threads color always clip your thread near the spool and pull your thread out from the bottom near your needle. When you pull your thread through the top little pieces of the thread break of and fall into the chamber of your embroidery machine .

See if you can discover how to reset the machine. Typically it is a combination of buttons pressed either simultaneously or in order as the machine is starting.

wiper error can come from the needle threader not working right, the cutter not working right or the picker not working right, i would recommend taking this to a dealer for service because setting the picker is easy but you have to be in the service program of the machine

These machines are known to freeze up in the needle bar crank, even when only a couple of hours old. If it is less than a year old, a Brother certified service center will fix it under warranty.

My PR600II error message main rotate error. what can i do to fix it

There should ba a screw that can be loosened enuf to remove broken needle. Be sure to replace new needle with flat side in the same way as the old one, otherwise thread will keep breaking.