On the bottom of the mirror there is a box with blue and yellow wires coming out. That is a control box and the litle thing sticking out is a capacitior, which gets fried over time(at least mine did). All the components are molded in compound, so they couldn't change anything execpt for the whole box.
My mirror stopped working and I exchanged the boxes left for right but to no avail. Probably the motor is dead, but the question is, what stopped first, the motor or the control box. And I didn't use the folding function at all. Maybe I should have.