Auto-disabling anti-theft systems include steering wheel locks, kill switches and tire locks. Some car warranties prohibit the installation of kill switches, making them less common, but steering wheel locks are very popular with automobile owners as of 2015.
Steering wheel lock manufacturers design their products to immobilize the steering wheel of the car, preventing thieves from driving it. The drawback to these products is that they do not prevent access to the automobile, making it possible to steal most of the interior components.
Kill switches work by disabling the electrical system of the engine. Many automobile manufacturers build kill switches into the anti-theft systems of their cars as a standard feature. Automobile security companies also install kill switches on cars for clients, but certain manufacturer warranties consider this to constitute tampering with the engine, voiding the car's warranty. Car owners installing a kill switch on a car should hide the switch in a location where it is difficult to find, since a thief may be able to spot it and disable the switch.
Tire locks operate on the same principle as the locks that parking enforcement agencies typically strap to tires when drivers park illegally. These locks are very visible and make driving impossible, but are difficult to unlock and unwieldy to use on a daily basis.