The Remote Transmitter
Both the keyless entry remote and the receiver system generate the same numbers each time because even though there is a random element the number generation will follow a built-in formula that will lead to the same result in each component. This formula is so accurate that a remote that has become out-of-sync by having the buttons pressed while out of range can still be used; the receiver can use the formula to recognize codes that would be generated by an out-of-sync transmitter. The receiver can predict up to 256 future generated numbers before the system will need to be completely resynchronized (a process which should be detailed in the owner's manual of the car or the keyless entry system).
A number generator within the control chip generates a semi-random number after transmitting the current security code; this generated number will be the new security code that will be transmitted next time a button on your keychain remote is pressed. This security feature ensures that not only will your remote not accidentally work with other cars but also that even if someone were to get a copy of a security code used by your remote, they won't be able to use it again to gain access to your car.
Transmitter and Receiver Synchronization
The number generator used by a keyless entry remote is considered to be only semi-random because there are two copies of the number that have to be generated and used together.Though the exact components contained within a keyless entry remote keychain Testament differ depending on the manufacturer and the year in which the keychain remote was created, there are a sporadic current parts that Testament develop in all keyless entry remotes. The two most exigent of these are the transmitter (which sends a expression to your vehivle in line to let it discriminate which Press-stud you've pressed on your remote) and the domination chip (which generates the security principle that lets your van be schooled that the vocable is outlook from a absolute keyless entry remote.) The radio signal sent by the transmitter will be picked up by a receiver built into your car, allowing it to recognize the security code and perform the action appropriate to the remote button that you've pushed.