The assemblies of the wiper and blade should occasionally be inspected for damages, loose parts and cracked or worn blade components. Film sprayed on the road may accumulate around the wiper blades and reduce their effectiveness; hence they must be washed with mild detergent regularly. The wiper mechanism's action can loosen nuts, bolts and fasteners so such should be tightened if needed when checking the wiping edges. Conversely, if the wiping edges are broken, worn down or distorted, or no longer cleanse adequately, new ones should be fixed. Lift off arm assembly from glass to clear it as then push to release lever then slide out your wiper blade assembly out of the hook at an end of an arm. To separate out a blade holder you will have to push a release pin in a direction as shown by an arrow and pull the windshield wipers towards this direction. Attach a fresh windshield wiper onto that arm: you'll hear it click into position.