Why is there an area in the middle of the windshield wiper that cannot be wiped?

[Oscar]

If the new wiper cannot wipe a section in the middle, it may be due to an oil film on the windshield. If it is a beamless wiper, it could be because the pressure from the wiper arm is insufficient, preventing the wiper from fully extending. It is recommended to replace the spring strip on the wiper arm or switch to a three-section wiper. A wiper is a blade structure installed in front of the windshield, composed of a motor, reducer, four-bar linkage, wiper arm spindle, and wiper blade assembly. Its main function is to clear rain, snow, and dust from the windshield that obstructs visibility. Reason: The wiper arm contains a spring, 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 spring-loaded wiper cannot adjust the downward pressure; it can only be resolved by adjusting the angle of the wiper. Wiper angle: If the wiper angle is incorrect, 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 angle of the wiper head is incorrect, the wiper blade may not fit properly against the windshield, leading to incomplete cleaning or areas that are not wiped. In such cases, lift the wiper, remove the wiper blade, and use a wrench to adjust the angle of the wiper head until it fits snugly against the glass. The method for replacing a car wiper is as follows: lift the wiper; press the clip below to remove the wiper blade; take off the wiper; pry up the front end of the middle clip; insert the wiper into the middle clip, pull it tight by hand, and once you hear a click, the replacement is complete.