Before you take the plastic scuttle cover off mark the parked position of the wipers by putting some tape on the windscreen at the blade ends so you refit them in the correct place. Take the wiper arms off, you may need a puller to prise them off their splines. Once off then remove the plastic securing pins that hold the cover on and lift it off to reveal the wiper motor and workings. Remove two bolts/nuts that hold the unit to the car, disconnect the electric plug and the white plastic clip that holds it in then lift the unit out. Fit the repair clip after first giving the joint a dab of grease. Whilst out turn it over and remove the six bolts that hold the cover plate on and once off clean the grease off the white plastic contact plate that is revealed. Grease migrates over this from the worm drive gear over time and upsets the parking position of the blades. Cleaning the grease off restores good contact and allows the blades to park in the correct position. Refit it all in reverse order.