Ok, I decided to clean the motor of my Bernina 707 this morning. One of the carbon brush was worn off to the spring and there was a lot of black dust. So I carefully dismantled everything, cleaned the commutator with an eraser, put new carbon brush and put everything back where it was. I was so proud of myself...
When I plugged the machine, the light was ok. But when I pressed the foot pedal... nothing happened.
I assume I must have put something back in a wrong way, but before opening it all again, I would like to have some clue about what could be wrong. A twisted wire? A loose screw? Would appreciate any idea.