The sweep for windshield wipers is set at the factory for maximum visibility and efficiency. In the event someone has removed and reinstalled your wiper arms improperly or the arms have been damaged, they may no longer sweep this path properly. Luckily, the design of most wiper arms is such that you can adjust the sweep. Anyone with basic auto repair skills can adjust the wiper arm sweep in less than 30 minutes on most years, makes and models of vehicles.
Lift the wiper arm base cover upward to determine how your wiper arm mounts to the wiper stud if so equipped. Most wiper arms use one of two mounting methods. The most common is with a nut that you can remove with a socket set or an Allen head set-screw that loosens with an Allen wrench.
Loosen the wiper arm from the wiper stud with the sockets or Allen wrench, depending on your vehicle's year, make and model.
Lift the wiper arm straight upward off the wiper stud. Turn the wiper arm to the desired sweep starting position then lower it back onto the wiper stud. Note that the wiper arm and wiper stud are splined, allowing for incremental adjustments.
Tighten the wiper arm to the stud in the reverse of how you loosened it. Lower the wiper arm base cover back into position if so equipped.
