Yes and no. Yes in that you can buy the key and cylinder so the key will turn the cylinder. And no in that the key is not the real issue. The BCMs security system has to be programmed to read whichever key you have, that is not something that the average DIYer can do.
Starting with the earliest system VATS with the resistor pellet - The key cut itself just allows the cylinder to rotate. The pellet in the key creates a specific voltage drop that tells the SKIM that "yep this is the correct key, go ahead and turn on the fuel and ignition"
The earlier transponder systems use a piece in the key that is very similar to the security tags in stores, The key goes into the ignition and the SKIM sends out pulses to read that security tag. If it matches the information the module has stored, the ECM receives a unique coded string of pulses that tells it that you have the correct key and it can start.
The current systems are even more elaborate. They use both passive and active coding in the fobs. This is what allows you to have the push button start and remote operations.
These systems also allow for different key coding in the security. So you could have one key that allows everything in the car to operate and sets the various items to that persons preferences, another as a valet key that only allows specific items to operate and even something like a teenager key, that restricts the power output and drive times and activates the navigation to record where the vehicle goes.
All of them require the SKIM/BCM to be programmed to the particular key(s) used.
Thursday, March 23rd, 2017 AT 1:24 PM