Windshield wiper blades should be inspected for wear or cracking. See Scheduled Maintenance.
It is a good idea to clean or replace the wiper blade assembly on a regular basis or when worn. For proper windshield wiper blade length and type, see Maintenance Replacement Parts.
To replace the wiper blade assembly:
Allowing the wiper blade arm to touch the windshield when no wiper blade is installed could damage the windshield. Any damage that occurs would not be covered by your warranty. Do not allow the wiper blade arm to touch the windshield.