Between the keypads, keyless entry systems and conventional locks, some cars today have four or five different ways to unlock the doors. How do cars keep track of all those different methods, and what exactly happens when the doors unlock?
The mechanism that unlocks your car doors is actually quite interesting. It has to be very reliable because it is going to unlock your doors tens of thousands of times over the life of your car.
This article was taken from: https://auto.howstuffworks.com/power-door-lock.htm