A: Every year or when the blades fail to clean the glass, they should be removed and new ones fitted. Pull the Wiper Arm/blade assembly away from the windshield glass against the tension of the wiper arm spring. Depress the small tab which lies just below the wiper arm at the blade connector socket and pull the blade from the arm. Note: On some models a coil spring blade retainer is used. To remove the blade, insert a screwdriver on top of the spring and push downwards. Depress the button and slide the rubber element off the wiper blade. To install a new element, press the button and slide the new piece into place. Once centered on the blade it will lock into position. Installation is a reversal of removal.