Pretty sure it is a whole new mech. If I remember rightly, the wire goes round a drum a few times the is driven by the motor. It is a sealed unit (I may be remembering my old Escort one tho
)
I would check it over carefully tho, as a broken wire could have got jammed up and caused other damage.
It would probably be cheaper and easier to just swap out the unit tho. Get one from a scrappy or ebay for a few quid and it is a nice easy job to swap them out.
Drop the window down a bit (or hold it up as needed) Undo the 2 bolts that hold the window onto the "gripper" bit. I held mine up afterwards with some masking tape (lots). Undo the 3 bolts that hold the unit in. Wiggle it free and undo the electrical connection. I think you have to slide the connector sideways, or part of it.
Reverse the job with the new one. Don't do the gripper up tight onto the window. Close it all the way, then either reach up behind the rather annoying door frame, or carefully wind the window down a bit to tighten the 2 bolts on the gripper. Took me about 30-45mins in the dark for a rear unit first time. Just make sure the glass is in its runners properly, and you have the wires on the right side before you do it up
