Clean the foreign bodies on the glass and check whether there is oil film.

Point 1, first check whether there are foreign objects on the glass, such as branches and parking belts, and clean them up first.

Another thing that 1 is easily overlooked is that the oil film on the windshield will make the glass surface uneven. When the wiper is used, it will rub badly and produce abnormal sound.

The method of judging whether there is oil film is also quite simple. Spray some water on the glass. If only a small area produces uneven water film, there is always toothpaste at home, right? Wipe, touch and brush are just a little easier.

But if the water film of the whole windshield is uneven, the oil film is serious, the toothpaste is not cheap, and the effect is not as good as the special one, you need a special degreasing film with stronger cleaning effect.

Check whether the wiper strip is aging.

The second point is to see if the rain is aging. Huang Guangtao of Southwest Jiaotong University published his master's thesis, Analysis of Vibration and Noise Characteristics of Wiper System.

It says: when the wiper changes direction up and down, the edge of the rubber strip will turn over, which will produce complicated reversing noise. The rubber strip blade of the new wiper is quite soft, so it can be easily flipped back and forth when scraping up and down.

However, after the blade ages and hardens, the elasticity is not so good, and the surface is pitted. When the wiper changes direction, it is easy to shake, making a "click" sound, and some even jump.

The wiper arm and motor are out of order and need to be repaired.

Continuing with the third point, this situation may be rare. The sources of abnormal noise are wiper arm and motor. For example, the angle between the wiper wall and the glass is not parallel to the naked eye, the wiper spring rusts, or the wiper motor fails, which will also lead to abnormal sound of the wiper. In this case, you'd better go to a professional garage.