1. Pull up the wiper and touch the wiper rubber after cleaning with your fingers to check whether there is any damage and the elasticity of the rubber blade. If the blade is aged, hardened and cracked, it needs to be replaced;
2. When it rains heavily, it feels good to use the wiper, but when it rains lightly, it is found that the wiper leaves uneven wiping marks on the glass surface, which affects the vision, which indicates that the wiper has hardened and needs to be replaced;
3. When the tension of the natural rubber wiper blade arm spring becomes weak, the wiper arm needs to be replaced. The wiper blade is in close contact with the windshield by the force of the wiper arm spring. When the tension of the spring becomes weak, the wiper will float due to the strong wind pressure brought to the windshield by high-speed driving, resulting in part of the glass not being swept. , it is best to update the wiper arm at this time;
4. If the glass surface is foggy, fine water droplets, streaks or partially blurred when the wiper is working, this is due to the influence of oil film, dirt or car wax. At this time, there is no need to replace it, just replace the windshield and wiper blades. Just clean it up. If the wiper is partially aged or worn in a small area, you can use 2000 grit sandpaper to polish the wiper, because the wiper itself has a certain thickness, so if a thin layer is polished off, it can still be used normally. However, when grinding, you must pay attention to the uniform grinding of the entire wiper blade. Generally, the wipers should be replaced every six months to a year.