The keyless entry system is one of the most advanced services that helps protect your vehicle from theft. This function can not only distinguish strangers from our own, but also unlock doors, remember seat settings and much more. For the first time, an SBDA combined with a power unit start button appeared about 20 years ago on a Mercedes-Benz S-Class. Currently, this technology is not considered luxury. It can be found on many budget cars, including Kia Rio and Volkswagen Polo.
How it works
The driver touches the door handle. The electronic control unit (ECU) for keyless entry receives a signal from a sensor located in it. After this, the control unit searches for the key, which should be no further than one and a half meters from the door. If all conditions are met, two-way data exchange begins between the key and the car. The process takes place in two stages: the ECU sends a signal to the key, and it responds.
After the first acquaintance, the ECU must make sure that the key is genuine. To do this, he resends the encoded signal, and the key must send “feedback”. If identification is successful, the ECU communicates with the comfort unit, which gives the command to open the locks. The system is very reliable in terms of signal encoding - the dialogue between the key and the car lasts such a short time that attackers do not have time to intercept and process the signal.
How to prevent theft if your car has SBDA
Perhaps the most obvious way to protect yourself is to remove the battery from the key fob.
However, most motorists are not ready to use this method every time they leave the car. Some automakers offer metal cases for key fobs that supposedly shield the signal. But it still manages to be intercepted, so in practice this technique is ineffective. It is most reliable to equip the car with a set of security components, which will include both electronic protection and mechanical locks - on the gearbox or steering wheel. A PIN code on the ignition or a GPS tracker wouldn't hurt.
Thanks to such measures, the degree of vehicle security will increase significantly and the car owner will be able to fully enjoy the benefits of the SBDA.
What does it consist of?
An electronic key can be made in the form of a classic key with buttons, a key fob or a smart card. The functionality depends on the brand and level of equipment of the car. Inside the key is a microcircuit that encodes and decodes the signal. To do this, it uses a floating code algorithm, which is considered one of the most reliable today. The antenna is used to receive and transmit encoded signals.
Electronic key
Electronic key
Sensor in door handles
Sensor in door handles
What is keyless entry
Not all domestic car enthusiasts have an idea of what this service is. The main purpose of the system is the ability to control the vehicle remotely. In some cases, the motorist does not even have to press any buttons on the key fob. Another function of SBDA is protective. The system combines the capabilities of an immobilizer and an alarm key fob. Also, a number of manufacturers offer the ability to manage the service using a special application on a smartphone. This is a very convenient option, since the car owner can prepare the car in advance according to his wishes before the trip.
As for the cost of such a useful application for a vehicle, it all depends on the available functionality. It is clear that a system that can only open and close car doors will cost several times less. But if a car owner wants to equip his car with a full-fledged control system with the ability to configure options via a smartphone, then he will have to part with a fairly round sum of money.
Handyman
Will open the trunk
. You can open not only the doors, but also the trunk without contact. On some cars, you don’t even need to touch the button to do this, just move your foot under the bumper: motion sensors will record the command, the automation will unlock the lock and activate the electric drive.
Typically, two capacitive proximity sensors are used, located in the lower and upper parts of the bumper and determining the command position of the leg. This function only works when the engine is not running to prevent false alarms when parking.
Raise the windows and close the sunroof
. On many models with keyless entry, windows and hatches automatically close when arming. To do this, you need to touch the sensor responsible for closing and do not release it until the windows and sunroof close.
Starting the engine without a key.
A prerequisite for starting the engine is that the key is inside the passenger compartment. When you press the start button, codes are exchanged using exactly the same protocol as when opening doors.
If you do not first depress the brake or clutch pedal (depending on the gearbox), only the ignition will turn on. To turn off the engine, just press the button again.
Advantages and disadvantages
Of course, SBDA, like any electronic system, has its pros and cons. The positive aspects include:
- no need to fiddle with keys to open the car door;
- the trunk lid opens with a button, which is very convenient if your hands are busy with packages or other things;
- you can activate the heating of the power unit in the cold season without leaving home (only possible in a car with an automatic transmission);
- when getting into a car with the system pre-activated, the engine stalls, which provides additional protection if intruders have entered the cabin at that time;
- The system remote control is additionally equipped with a Smart Key key fob, which helps open the vehicle doors when the battery is dead.
With all the useful options of the service, it also has certain disadvantages. First of all, it is the inability to get into the car if the device is lost. Even if the car owner breaks the window, the SBDA will still not allow him to start the engine. In such a situation, the motorist will have to contact the automaker with a complete package of documents for the car in order to obtain a duplicate. And this, in turn, leads to additional financial costs (from 300 to 1000 dollars on average). Another unpleasant moment associated with the loss of a keychain is that it may fall into the wrong hands. An unscrupulous citizen can take advantage of the situation and take possession of the motorist’s property.
Why does not it work
- The key battery or vehicle battery is discharged.
- It is not recommended to store the key near a mobile phone: interference from its operation can lead to malfunctions of the keyless entry system and push-button start of the engine.
- Strong electromagnetic interference, for example near a television center, can reduce the range of reliable operation of the system.
- Door handle sensors don't last forever. Water, reagents and dirt corrode wires, and sometimes corrosion destroys sensors. The treatment is simple and inexpensive: you need to restore the connection and properly insulate it.
- On some vehicles, during repairs, the connectors for the high-frequency speaker and the keyless entry antenna may be mixed up. In this case, the system stops working. It is easy to calculate such castling. If the speaker is silent, you need to remove the door panel and connect the wires correctly.
Keyless access: main system vulnerabilities
Modern systems
It is thanks to the advent of modern digital systems that keyless access has been fully implemented. This is made possible by sophisticated coding of digital signals.
A so-called floating code has appeared for keyless entry.
The idea is that a large number of code options are generated. During preliminary interaction between the control unit in the car and the smart key, an arbitrary code is generated. These are millions of all kinds of combinations that are impossible to intercept, guess or copy.
Even if attackers manage to intercept the generated code, nothing will work if they try to use it. After all, the code next time will be completely different.
As you know, thefts are committed by criminals according to the following scheme:
One attacker stands near the car door with a special radio receiver-transmitter.
His accomplice at this time goes after the victim with a special radio amplifier. Its task is to catch the low-power signal from the key fob, which it sends even in idle mode and with the help of a repeater-amplifier, and send the signal to a fake key fob, which will then open the car.
This “fishing rod” method allows you to open cars even if the key is not nearby. For example, criminals very often use this method in parking lots at large shopping centers, when they track down the desired car and, having split up, carry out a criminal operation. In this case, one of them will follow the victim, reading the signal from the key fob with equipment (it is simply placed in a briefcase or bag), and the other will open the car, start it and drive away.
Or car thieves will scan a private house with a car parked nearby. An example is in this video:
Video taken from YouTube channel “Newsflare”
Or, using similar equipment, pass under the windows of high-rise buildings if they know for sure that the theft victim lives on the first or second floors.
Thus, after the above manipulations, the intercepted car opens and the engine can be started.
Surprisingly, despite the fact that the safety issue and system flaws have been known for years, the vast majority of automakers have not lifted a finger to help their customers avoid major problems.
There are only a few car manufacturers in the world that equip their cars with additional technology that allows the receiver to recognize whether the car key is actually near the car or whether it is only receiving a radio signal to unlock it. This is the so-called ultra-wideband technology (UWB). Used primarily in Jaguar Land Rover vehicles. The VW Golf 8 is also equipped with it.
photo: Apple
The next generation iPhone will also use UWB technology, Apple announced this during WWDC this year:
“Apple also confirmed that the company has already begun work on the next generation digital dongle, which will use ultra-wideband technology and the U1 chip. This will allow owners to unlock their cars without removing their iPhone from their pocket. It will be available next year."
And yes, now some cars can be opened using phones with a bitten apple: iPhone as a car key: which BMW will open?
About hacks
Of course, attackers are well aware of the operating principle of the smart-key system, and their main task is to catch the signal sent from the key fob to the car lock. For this purpose, they use a special radio scanning device, thanks to which they receive an access code to the car alarm system. After which all they have to do is send the received data to the system, which responds to “its” code, turns off and provides access to the car. The sad situation is further aggravated by the fact that such scanners can be purchased completely freely, and their cost is low.
How cars with the Keyless Go system are stolen
The entire theft happens quite quickly, sometimes in a matter of seconds. The attacker transmits a signal from the contactless key to a radio receiver in his hands. Now such equipment can be bought at any radio electronics store or ordered online.
After purchasing such a product, a process begins when criminals look for a suitable car to steal. The main thing is that it is equipped with a contactless access system. Sometimes it’s quite easy to find such a car, because... It has a button inside that starts the engine. Next, everything is done according to the thumbnail pattern.
Mechanical protection of the car
You can also purchase an additional security system. For example, the best solution would be to install mechanical protection - a steering wheel lock, a gearbox lock, a brake pedal lock, etc. You can also buy a special wheel clamp.
By installing mechanical protection on your car, you create an extra barrier for criminals and additional difficulties for stealing a car. After all, having gained access to the car using special equipment, they will be faced with mechanical protection, which takes time to break. Most likely, in this case, the hijackers simply retreat, since in this case there are great risks for them.
About protection
According to experts, the owner needs to store the smart key to his car in special boxes made of material that suppresses the radio signal that is constantly exchanged between the system and the key fob. You can wrap it in aluminum foil, which can muffle the transmission of information.
In addition, we should not forget about the high level of effectiveness of mechanical anti-theft means, in particular, locks that can be installed on the pedals, steering column or gear shift lever. With such devices, it will be extremely difficult for criminals to steal a car, even if they manage to catch the signal from your key fob.
As an option, you can consider the possibility of flashing the system itself, which will work according to a system different from the standard algorithm. This can be done in specialized centers; as a result, the modernized smart key will mislead attackers and cope with its functions more effectively.
