1, p file. That is, parking gear and parking gear, the mechanical device in the gearbox is used to lock the rotating part of the car. Only when the car comes to a complete stop can P gear be used, and the car must be in P gear when it is turned off.
2.r file. Reverse gear, as the name implies, is to shift gear when reversing. It should be noted that under the condition that the vehicle is not completely stopped, do not forcibly shift the R gear, which will cause the transmission to wear.
3.n file. Which is neutrality. Generally, when parking for a short time, there will be a neutral position. At this time, your right foot can leave the brake pedal to rest. But if it's uphill or downhill, you still need to step on the brakes, otherwise it will slip, unless you pull the hand to brake the electronic brake.
4.d file. In the forward gear and drive gear, when shifting into the D gear, the driver only needs to control the accelerator pedal to control the vehicle speed, and the transmission will automatically determine the gear according to the accelerator size and vehicle speed without manual gear shifting.
Extended data:
Vehicles equipped with automatic gears are more continuous and accurate in shifting gears, so they are more fuel-efficient on urban roads, and the fuel consumption at high speed is equivalent to that of manual gears. Because the automatic transmission adopts hydraulic transmission device, the acceleration is lagging behind, which will make people who often drive manual transmission feel "slow" and "fleshy". However, some excellent automobile manufacturers can minimize the lag time and meet the requirements of car owners for driving pleasure.
Automatic gearbox is generally composed of hydraulic control system and planetary gear set. If you slide in neutral (N gear), then the engine is idling, and the sliding speed is higher than idle speed, resulting in insufficient oil pressure in the hydraulic pipeline, which will increase friction and reduce lubrication effect, and may lock the wheels.
People's network-control automatic cars pay attention to these points!