Cars, like humans, sometimes have a fever and a cold, just like everyday life. Many new car drivers also look at some of the small malfunctions of the car, but many times because they do not solve the car, so often "misdiagnosis", the original small book is magnified to replace the entire component, which is a waste of time and waste of money. Next, we will give some examples which are often easily misdiagnosed by the driver. The back door could not open the rear seat passengers to get off, but it was found that the door could not be opened. The novice may think, "no, it looks like the door lock is broken." In fact, this is just a child's safety lock. In order to prevent children from accidentally opening the door from the car, many vehicles are equipped with children's locks. If the device is accidentally started, the rear door can only be opened outside the car. In this case, just close the child lock. Some children's locks are located at the door handle of the rear door, and some cars arrange the lock position on the side of the back door. Only when the door is opened can it be adjusted. The air conditioner is not cool enough. Some newcomers often envy the air conditioner in other people's car so cool, and their own car handles the air conditioner to the maximum. At most, it feels "not too hot", and it takes a long time to cool down in the car when it starts the air conditioning under the sun. You probably ignore the role of the inside and outside loop buttons. If the vehicle starts the air circulation inside and outside the air conditioner, the cooling effect will obviously decrease, but the advantage is that the air is fresh. On the contrary, if the internal circulation of air-conditioning is used simply, the cooling capacity will be greatly improved, but the disadvantage is the lack of internal and external air exchange, and the air in the compartment is not fresh enough. When the steering wheel stuck in the vehicle, it was surprised to find that the car key was unscrewed, or the steering wheel was stuck. In this case, don't think that the car was broken. Please repair it because it was just the lock of the steering wheel of the vehicle. The steering wheel is automatically locked after parking. This is a very common function on cars. Although compared with most electronic burglar burglar devices, the steering wheel lock appears original, but for the thieves, even if the car is successfully started, the steering wheel can not be rotated, so it still has a good anti-theft function. The hanging feeling is too hard and clear when buying a car feeling very comfortable, how to open up so hard now, and when sitting the same style of other people's car, did not feel so strong bumps. In this case, we should pay attention to check whether the tire pressure is too high. The tire is a very important shock absorber in the car. When the tire pressure is suitable, the tire can absorb the bumps well from the road, but if the tire pressure is not suitable, especially the tire pressure is too high, the tire loses its ability to shock absorption. Fuel consumption is too high, novice often headache, there is a big problem, that is fuel consumption. Fuel consumption is the most important criterion to distinguish novice and veteran. Novices not only do not know enough about routes, but also do not have enough knowledge about vehicles. Manual manual blocking, frequent low gear or high speed and low speed will have a great impact on engine and fuel consumption. Open automatic block, novice do not know how to use the throttle depth control gear, high fuel consumption is reasonable. The above situation may be rare in the driving process of the old driver, because the day after the practice will have a deep understanding of the car, each button knows what to do with it. But it is inevitable that some new drivers will be nervous when they encounter this situation. This is due to the ignorance of the function of the car. There are many similar examples, which tell us not to be too nervous when some surface faults are encountered, perhaps just a small button that gives us a wrong judgment.