(6) Causes of Battery Instability: Abnormal electrolyte changes affect battery performance and reliability. Maintenance method: When driving in summer, the battery is overcharged, the electrolyte evaporates quickly and the electrode plate can be easily damaged. It is therefore necessary to check the battery fluid level and the specific gravity of the electrolyte frequently and to add distilled water to the battery frequently. Avoid completely discharging the battery in winter and make sure that the electrolyte is frozen.(7) Wiper scratch glass ineffective reason: wiper blades appeared to be damaged, can lead to scratching not being clean.Maintenance method: First, the owner has to correct the bad habit of dry scraping. It is best to spray some water before turning on the wiper, which will help protect the wiper blade. Second, the wiper sometimes makes a gurgling noise. If at this point the wiper blade is ready, the owner should go to the 4S shop to correct the wiper angle. If the vehicle is parked for a long time, the owner can find small things like foam strips or wooden strips and place them under the wiper to separate the wiper blade and the windshield.