To work on the wiper arm, cycle the wiper arm into PARK mode and shut off the ignition. Pick up a trim stick (special tool C-4755) or an alternative one and gently lift the cap that holds the retaining nut to remove it. After that, loosen and remove the retaining nut from the part where the wiper arm pivot attaches. Lift the arm up so the
Wiper Blade is clear of the windshield, rock it left and right while it's on the pivot and then take it out of the car. When installing, secure the wiper arm to the wiper pivot and attach the retaining nut to the arm pivot. Later, fit the wiper arm retaining nut cap as directed by the manual. Next, move the wiper blades back and forth a few times so the arms are in the right place; make changes if needed.