Removing the folding table and opening the seat
When the seat has a folding table unscrew the two upper Torx 20 screws (pic01).
At the bottom the folding table is held by two plastic clips. When the screws are removed pulling the table away from the backrest will release the clips (pic02).
Now the lining at the back of the backrest can be taken off. It's zipped with black plastic strips on the sides and bottom (pic03).
When the lining is loose it can be lifted and the inside of the seat is exposed. The two diagonal black wires at the upper part of the backrest were the trouble causers in my case (pic04).
They rub in two holes near the headrest (pic05).