Keyless entry to the car is one of the popular options that drivers choose when buying a new car. Let's talk about the principle of operation and the structure of the system.
The content of the article:
- A little about the system
- Device and mechanisms
- How keyless entry works
- Advantages and disadvantages
More and more often, you can see cars that close or open the door locks themselves, warm up the engine on their own, or may even come to the specified place. Keyless access to the car can be considered a popular system of a modern car.
What is keyless entry
Often, drivers who have never seen a keyless entry system wonder what it is and how it works. The main purpose of keyless entry is to drive a car from a distance, often without even pressing the buttons on the key fob.
The second function of the system is to protect the car, this system includes the functions of an immobilizer, protection against theft through various calculations and functions. In addition, some manufacturers offer smartphone control. The driver can fully control the car remotely, having prepared it in advance according to his wishes.
The cost of such a system will depend on its capabilities, open or close the doors, the trunk lid will cost less, but control from a smartphone and full control of the car will pull hundreds of dollars of additional costs.
Composite Keyless Entry Mechanisms
The keyless access to the car can be divided into two parts. The first is the device itself and the mechanisms in the car, the second is the key fob, the so-called Smart Key, which is located at the driver's side.
The device in the car is a whole set of mechanisms, and in order to start the car, you do not need to stick the key into the ignition lock. With such a system, it is enough to press the engine Start / Stop button on the front panel. Some manufacturers for reassurance use a special socket for additional confirmation. The driver will need to insert the Smart Key there to read the special code from the key and verify the identity.
Let's consider what the system consists of on board a car. As already mentioned, the presence of such a system is indicated by the Start / Stop button on the front panel near the steering wheel. Next comes the control unit itself, it is based on a small computer and a fairly powerful radio system. It is due to the radio system that all control takes place.
Typically, each control unit has its own separate frequency for operation, but some manufacturers use two or three frequencies. It can also be a GSM network for remote access from a smartphone. Such a control unit acts as an input device and a data processing device.
As for the executive devices, there is no definite list, often the main ones are considered:
- central locking (for opening / closing doors);
- engine start / stop button;
- trunk lid control.
Manufacturers of premium cars often add climate control, GPS navigation control (remotely you can see where the car is) and many other functions, up to the wishes of the driver.
The second part of the keyless entry system is the key fob itself or, in another way, Smart Key. The keychain itself is somewhat similar to an alarm keychain. It often has at least three buttons on it. These are opening / closing doors and a button for opening the trunk lid. In more advanced systems, there may be a Start / Stop button for the engine or some other bells and whistles, since each manufacturer makes the system differently. Premium car manufacturers allow you to replace the Smart Key with a smartphone by installing special software on it. Although it often happens that Smart Key works in tandem with a smartphone. What will be the keyless entry system and its device can only be decided by the manufacturer, the buyer will see the final result.
How the keyless entry system works
The basis for the creation of a keyless entry system was the usual and familiar car alarm system. As mentioned, keyless entry is radio frequency based and is an active system. Basically, this system cannot be disabled or reconfigured.
The control unit constantly operates in the receiver or transmitter mode, waiting for signals from the Smart Key fob, which is at the driver's side. The control unit sends signals from time to time to check where the access key is. A special chip with an encrypted code is embedded in the Smart Key fob. It is this microchip that constantly sends signals about its location.
So, what does the keyless access system start with? Imagine a situation when a driver leaves the car, often the Smart Key is stored in a pocket or on a belt, in a special case. Having closed the car doors (not with the key), the driver moves away a certain distance from the car (as a rule, the radius is 2-3 meters), as soon as this distance is exceeded, the system automatically closes the doors and raises the windows.
If the driver approaches a close distance to the car (the reverse process, in this case the distance is about a meter or two, that is, less). Smart Key sends a signal that the driver is approaching, and the keyless entry system automatically opens the car doors. It also lowers the windows, if provided in the control unit.
If a smartphone is used, then the basis of such a system is a Bluetooth or Wi-Fi network, rarely GSM. Often this is Bluetooth, since the low power consumption and operating range are within normal limits. The software sends a specific encrypted signal with a code, thereby informing the keyless entry system to close or open the vehicle.
As mentioned above, keyless entry serves the same function as an alarm and immobilizer. An encrypted signal is not so easy to pick up in modern cars, which means that you will not be able to turn on the engine in any way. Some manufacturers went for the trick by introducing the function of reading driver parameters into the keyless entry system.
For example, when sitting in the driver's seat, the system reads the driver's weight or height within the acceptable range. If the deviations are serious enough, you will be prompted to enter the password on the monitor of the multimedia system, but if everything matches, the car will start in the mode that the driver most often selects.
Pros and cons of keyless entry
Of course, the keyless entry system has both pros and cons. The pros are that there are fewer problems opening or closing doors. The trunk lid can be opened from the button on the key fob, and not go into the salon (especially when your hands are busy with something). It has become much easier to warm up the car in cold weather, looking out of the window, just press the button on the key fob, and before that set the automatic transmission selector to parking mode (often the engine warm-up function is available only with automatic transmission). Many manufacturers develop keyless entry in such a way that the steering wheel, brake and accelerator pedals are locked while the engine is warming up. In the event of landing, the engine automatically stalls, even if it is the owner of the car.
It is no secret that even the owners of stationary alarms have more than once found themselves in a situation where the battery is dead, and it is impossible to open the car from the remote control. So what about the keyless access to the car when the battery is dead?To do this, many manufacturers embed a regular key into the Smart Key fob, at first glance this is an eyelet for fastening, but by pulling it you can see the key.
But besides the positive aspects, there are also negative aspects. If you lose your Smart Key, you will not be able to get into the car. Even breaking the glass, the immobilizer will work, which simply will not allow the engine to start. In this case, you will only need to contact the car manufacturer to make a duplicate key.
Next, you will need to visit the dealership to reprogram the mechanism in the car. Whoever finds the Smart Key can take advantage of the situation and take over your vehicles effortlessly. The average cost of issuing a duplicate and reprogramming starts at $ 300 and can reach several thousand (as practice shows, these are cars from Mercedes-Benz, BMW, Audi and other elite supercars).
Still, there is no 100% protection against opening the car, modern information technologies allow to intercept the encrypted key on the fly and thereby steal the car. Good or bad system is up to the owner of the car to decide. For the most part, drivers choose this option and are content with using it.
