First off –DO NOT follow the advice of a “fraudulent” email being sent about the Internet, “How to Lock Your Car and Why!” The email is “kinda” true, as it may indeed apply to automobiles manufactured before the mid 1980s, when the Remote Key-less Locking Device for automobiles was first introduced.
According to Snopes.com, the email is doubly FALSE as it states that Snopes has approved the information in the email. In fact, Snopes has verified as FALSE the basic premise that car thieves, sitting somewhere in a parking lot, are using a new device that can easily grab and clone your security code as you lock your car using a key-less locking device. The email further states that police are advising people to thwart the thieves by using the key-less remote to lock a car while still sitting “inside,” before exiting. In this case, according to the fraudulent email quoting the police, the thieves cannot grab your code.
Before following the email’s advice, you would be far safer to lock your car the “old-fashioned” way, with the key in the lock. That is because locking your car, from inside the car, is far more likely to end up with you locked outside of your locked car, and your key, along with your children and pets, still inside.
Since the 1990s, manufacturers of these key-less entry devices have been employing rolling random codes which change each time the system is used to lock or unlock a car, thus rendering ineffective the car thieves “code grabber” devices. Automobiles manufactured after the mid-1990s, are not vulnerable to being quickly and easily opened by criminals armed with code grabbers.
Yes, a very determined and smart thief could thwart the system according to Keeloq. However, the thief would need specialized knowledge and then spend hours, if not days, crunching data in order to replicate a device to produce the correct entry code. The thief would also need to know that the vehicle would stay fixed in place during the time he was calculating the key code.
So — when you receive this email warning you about the use of your Key-less Remote to lock your car, be advised that the information in that e-mail is FALSE, and, in the interest of the personal safety of others, please do not disseminate it any further.