An auto switch, also known as an automatic transmission switch, is a component in a vehicle equipped with an automatic transmission. It is a small switch that controls the operation of the transmission.
The auto switch is typically located near the gear shift lever, and it is usually labeled with the letters "P," "R," "N," "D," and sometimes "L" or "S." These letters stand for the various gears that the transmission can be in: park, reverse, neutral, drive, low (in some cases), and sport (in some cases).
When the auto switch is in the "P" position, the transmission is in park. When it is in the "R" position, the transmission is in reverse. When it is in the "N" position, the transmission is in neutral. And when it is in the "D" position, the transmission is in drive. In some vehicles, the auto switch may also have a "L" position for low gear, and an "S" position for sport mode.
To use the auto switch, the driver simply moves the switch to the desired position to select the desired gear. For example, to put the vehicle in reverse, the driver would move the switch to the "R" position.