A keyless fob is a small device that has replaced a traditional car key. It is similar to a key fob, but in addition to unlocking and locking the doors, it is also used to start the engine. The main difference of a key fob and a keyless fob is reflected in its name. The keyless fob does not have a key attached to it. Car models that use keyless fobs come without a key and do not have a visible lock on the car doors. To start the engine, the user pushes a button on the dashboard. This is called Push-Button Start.
A keyless fob uses a short-range radio signal like a key fob. But with a keyless fob, the signal is also used to start the engine. The fob sends a unique signal that allows the user to start the engine with the Push-Button Start system. If the fob is not inside or near the car, the system does not work and the engine will not start. In a situation like that, the car usually warns the user that the key is not inside the vehicle.