Key Fob 101

Today if you buy a new or relatively new car you canenough to the car for the receiver to pick up the
expect it to come with a keyless entry system and atransmission than the two are no longer synchronized.
remote to operate that system. The remote is oftenThis problem is resolved very easily because a typical
referred to as a key fob because it is typically carriedsystem will have many other codes that it will accept
on a keychain. By definition a key fob refers toafter de-synchronization (usually 256). However, this
anything carried on a keychain for decoration ormeans that if you press the remote 257 times while
functionality, but most of the time when that term isnot in range of the car you could have a problem
used it is referring to the keyless entry remote. Theybecause the remote has no acceptable codes left to
have become just as much of a status symbol asattempt. In this case you will need to reprogram the
anything else, but knowing exactly how they work cansystem; a process that varies by make and model of
be very useful.the vehicle, but can usually be found online.
A key fob works like many other basic remoteFinally, keep in mind that because this technology is so
controlled systems. In the remote is a computer chipcomplex, key fobs are not interchangeable and cannot
that creates a very unique code that the receiver isbe copied. You need to take good care of that little
programmed to recognize. You do not need to worrypiece of plastic because if you lose or break it, then a
that someone could replicate this code because anew one will have to be purchased and programmed.
standard 40-bit rolling code is choosing from about aThis can be a costly process, but again it depends on
trillion possibilities. Also, the code that the system usesthe kind of car you have. For some vehicles there are
is not always the same and the remote and receiverjust a few quick steps to follow but for others a
need to be synchronized as a result. This is done uponprofessional mechanic (with the appropriate equipment)
installation of the keyless entry system so no need towill have to do it. I would recommend checking online to
worry about it.see if you could program a new remote yourself as it
There is one problem that can arise from this basicwill save you about $50-$100.
design. If you push the remote and are not close