A Brother dealer down in Florida told me that the automatic threader has been left off the newer machines, because it was such a trouble maker. Maybe you should thread the machine by hand and not use the auto threader.
Don't feel bad about having a problem machine. My Janome 11000SE refuses to boot up, until you turn it on/off 10-20 times. When I take it in for repair, the repair person cannot duplicate the problem. No, it's not my power supply. I've tried it in different places, different surge protectors, even different houses. Plus the light comes on at first, then shuts itself off. I am just living with it. Guess you'll have to do the same with your Brother:-(

I figured out the auto threader, it operates about 90% of the time,it is the channels, "tracks" that the thread goes through to pull it through the tension discs sometimes it doesnt pull far enough to the back to go under the flat plate that loads it into the tension discs, no way to tell when you are pulling the threads through, and no way to operate the machine when that part of the cover is off (so the repairman says) but if it keeps happening, I am going to try anyway.
Sorry about your machine, it sounds to me like a loose connection (wire inside of coating may be separating,see if it happens with another foot control), or the other thing it might be since light comes on then goes off, make sure the wattage for your light bulb is correct. I have a few Featherweights and if the light bulb is anything more than a 15w they heat up and then lock up until the machine cools down.
:D :-)

that was my first thought...I have 2 brothers 270D and 8500 and love both of them....sometimes the 270 has bobbin problems but works best with prewounds...

hi patdesign, i have the same problem with mine. mine jammed so bad they had to put a new part in it. after it cost 200.oo to fix. i can get it threaded right maybe 1 time out of ten tries. then i do get it threaded right and it goes a little ways then the thread breaks. i called the brothers manufacture and they just told me to take it to the dealer. it is ready to go back in to see wat i am doing wrong. the threading path is very touchy.i have only had my 1250D since xmas if u just do straight sewing u r fine its the embroidery thats the problem. sure hope they can fix it for me as i realy like the machine. good luck lorene

I use Polystar and have had great results.

http://www.mrvacandmrssew.com/sewing...es/thread.aspx

I have the 780D and I've noticed it doesn't like certain COLORS of certain brands. I've found two: Like sulky black. or a goldish yellow shade of Madera that is one of my school colors.

If I use the other brand of those two colors, she's fine. Unless I've used the wrong stablilizer. But I can't be mad at her because I don't know what I'm doing...

I've also found a few times as I thread a new color that a "clump" of the last thread color will come out, like it was fraying and about to break. Sounds like the start of your problem, but not quite there yet.

I have a Brother LB-6770 embroidery machine and I love it, have had no problems with it. My wife has a Brother 6000D embroidery machine (the huge one) and she loves it, too, great machine. For piecing, I use a Brother QC-1000 machine, which is wonderful. I can't say enough good things about Brother machines, love them. :)

hi i use madeira rayon thread. was told not to use coats and clark. ikno that your project can be to lose but some of mine i thought were to tight because of the strain on the project u r embroidering some of mywork was puckering

I have a Brother Innov-is 1500D. I've had it for about 5 years and I have never had any problems with it. I love this machine.

I have 3 Brother machines. They all do different types of sewing and I love them all!! I have a ULT2003D and use the embroidery a lot and have never had a problem. I use Madiera thread. Be sure you are using the right needle also. Make sure it is for embroidery and the right size.