What is the reason for a section in the middle of the wiper not being able to wipe?

[McChristopher]

If a new wiper cannot wipe a section in the middle, it may be due to insufficient wiper pressure. Here are the details: 1. Cause: There is a spring inside the wiper arm, and the wiper relies on the spring to provide downward pressure to clean the windshield effectively during its movement. If the wiper pressure is too low, it will result in incomplete cleaning. This type of wiper with a spring cannot adjust the downward pressure; the issue can only be resolved by adjusting the wiper angle. 2. Wiper angle: If the wiper angle is not optimal, you can loosen the screw at the base of the wiper arm, adjust it to the correct position, tighten the screw, and cover the dust cap. If the wiper head angle is not optimal, it will prevent the wiper blade from fitting well against the windshield, leading to incomplete cleaning or areas that cannot be wiped. In this case, you can lift the wiper, remove the wiper blade, and use a wrench to adjust the wiper head angle until it fits properly against the glass.