keep Away!
No matter what company made your sewing machine, if it has electronic parts then you cannot fool with them...even touch them. Why?
Static Electricity! a natural element that we usually associate with woolen socks and rugs producing a spark. But you produce static electricity all the time and you aren't aware of it.
If you touch a circuit board, for example then you have run a high risk of disabling it. Bernina technicians have special grounded mats and wrist bands which drain the static from their bodies. Your machine is placed on this mat before any work is done, even cleaning and oiling...if certain circuit boards are involved. Don't blow your circuits! If you have another brand of machine that uses electronic elements then the same thing goes. We, however, are Bernina dealers and our comments will emphasize them.
This picture shows the top of an electronic Bernina. The arrows point to screws which, when taken out reveal some of the circuit boards. NEVER TAKE THESE SCREWS OUT. Never allow friends or the "Sewing machine repair person" who has always done such good work on your other machines to take these screws out. If the top is removed by someone who is not properly electrically grounded, then the machine's circuit boards will be fried. You won't hear anything. No snap, crackle, pop. Just don't take the top off. There's nothing there you can adjust anyway.
Now, the next picture shows a machine where the arrow is pointing to the bobbin case door. There is a big black colored sensor attached to the door. The sensor has wires coming out of it and it has to be precisely positioned. Don't take the bobbin case door off the machine The white cover that encloses the door and wraps around that part of the machine would be tempting for you to take off in order to clean. However, the door would have to come off with it and the cover is a devil to get back on if you don't know what you are doing: Keep away!
In another installment, we'll talk about taking the face plate off and understanding what is hidden underneath, cleaning and oiling it. (The face plate is the white cover that has the pressure foot adjustment knob on it (just above our arrow).
The picture below shows, of course, the handwheel area of your machine. Many times we have to service a machine on which we find yards and yards of thread wrapped on the inside of the handwheel It can't be seen, but the machine runs very slowly as the thread binds up. How does this happen? If you are using two spools of thread--you know, one spool in the second thread holder--and you leave one spool in place when you go back to one spool work. In that case the second spool is dangling a loose end down and this end can get caught in the handwheel, wrapping itself round and round without your knowledge. Your first solution is to take the second spool off when you are not using it. If thread wraps then you'll have to get some servicing done. To do the job right all the covers have to be removed...a job you are heartily advised to not do and to not have the friendly repairman down the street do for you. The warnings about circuit boards detailed above apply even more here.
