Ford escort rear window wiper problem?

my rear window wiper doesn't work properly when i turn it on it is very slow and stops on then middle, also when this happens it lights up the rear demister and fog light. if i push the fog light button it makes the wiper move about an inch. ive had a play about with it today by cleaning the contact plates and the earth connections. still no joy. i then unplugged the 3 pin connector by accident forgot what way the wires go on and blown a fuse. i replaced the fuse turned on the ignition and now then bloody wiper wont stop at all lol not Even on the switch. after scratching my head i decided to unplug all the wires from the contact plate on the bottom of the luggage compartment now my fog lights work perfect and so does my demister but no window wiper. so what is the problem?? maybe the relay is had it. could anyone shed some light please.