In the evening, Ms. sun was ready to drive home. When it was started, it was found that the car could not catch fire and heard the sound of bating when starting. Ms. sun hurriedly called the 4S store's rescue. The rescuers told her that the battery was dead. Ms. sun has checked the work in the morning. The air conditioning and lighting are all closed. There is no electrical equipment. Why does the battery suddenly lose power? I believe that friends who drive frequently will encounter the same problem with Ms. sun occasionally. 4S shop maintenance personnel said that in order to prevent the battery suddenly out of power, the best way is to pay more attention to the car's "help signal". The signal has the following forms: one is that the starter does not turn or rotates so that the starter can't start; two is the front headlight darker than usual; the three is the small or even no sound of the horn. If the above problems arise, the owner will check whether the battery is a problem. In order to minimize the power consumption of the battery, 4S experts put forward two suggestions: first, avoid lighting or listening to the engine for a long time, and second, if the engine is running, if the parking time is longer, it should be used unused electric equipment (the inside and outside lights and sound of the car). Power off, such as navigation, etc. Developing a good habit of using cars can avoid unnecessary dilemmas. However, in case of the battery suddenly no electricity, there are several ways to "self rescue": first, the car start is the most familiar and the most effective emergency starting method, but this is a method that can not be used, can not be used frequently, because it has a certain damage to the engine and the clutch, automatically block the car. In particular, it is necessary to avoid using this method to start. Two, in order to avoid charging the battery without electricity, the owner should prepare a jumper cable in the car, which can be bought in the general auto shop. However, when connecting jumper cables, you must never mistake the connection order of the jumper cable. First, connect the positive terminal of the battery without electricity to the positive terminal of the rescue car battery, and then connect the negative terminal of the rescue car battery with the metal part of the motor vehicle engine room (grounding wire). After connecting the cable, it can start the engine of the rescue car and improve the engine's speed a little. After about 5 minutes, the battery can be charged to the battery without electricity. After the charging is completed, the jumper cable should be removed in the reverse order with the connecting jumper cable. The most reliable way is to contact the rescue vehicle in time, then connect the jumper cable and temporarily charge the vehicle through the rescue vehicle to start the engine. Finally, experts remind that battery life is usually 2 to 3 years. After this time limit, the vehicle pays special attention to the maintenance of the battery normally. If necessary, it should be replaced in time to avoid any danger.