Common water damage?

I left the car door cards off a few nights and didn't have those protective covers on them either and I guess some of the electrics have been water damaged.

All is fine except the right rear passengers door. I replaced the door loom and window regulator, but it's still not working (central locking for that door and the electric window). I took a look at the wire that runs from the bottom of the rear door all the way to the bottom of the drivers door and past it. I touched the wire and it was soaking wet (This was weeks ago) and still now is damp.

Any idea what this wire is called?

Skoda octavia 1.8 20v 1999 automatic.