Replacing keys is not as simple as taking a remote control from an old car and programming it in your new car, even if they are of the same make and model. With newer cars, you will likely need to visit a dealer or locksmith to program a new key. However, you can program the key fob's unlock and lock function without having to go to the dealer. But if you need to program the transponder to be able to start the car with the key, you may have to go to the dealer or a locksmith. Reprogramming a key fob for the lock and unlock function is usually free if you do it yourself on most car models.
Most of the time, to program a key fob with push button start, the appropriate diagnostic tools are needed because of the immobilizer, which is usually only accessible to authorized distributors. If you just want to program the key fob to lock and unlock your car, you can usually do it yourself. Programming a key fob for the central locking system is usually a fairly simple task, but if you want to program an immobilizer, you may need to contact a professional. To test that your programming was successful, use all the key rings that have been programmed and verify their operation. When you hear the door close, press the key fob lock button again in five seconds and the programming should be successful.
Like any other electronic device, these key rings can stop working after a while, usually due to loss of signal or data. If your key fob has stopped working, it may be due to a dead battery or needing reprogramming. New vehicle keys now have a transponder chip and, as the key is inserted into the ignition, the chip is activated by the radio frequency signal sent from the ignition cylinder. To avoid problems in the future, it's worth replacing batteries in your keychain when needed.