If you push a screwdriver underneath (between the fabric and the plastic)either side of the lever at the top of the seat then plastic lever can be pulled from the top of the seat. If your lucky the lever has broken ,if not the plastic part which is attached to the cables is probably broken. I think this and the cable are all one piece,and you'll have to replace the cable mechanism. The lever on the top is about £14 from Fords.
Paul b
May 2008