Your garage door opener itself has what they call 'Rolling Codes' if you take the cover off your garage door opener you should see a button somewhere on it labeled 'Reset' or 'Learn' if you press that button after you clear your car of it's codes as well (hold the outside two buttons until it flashes fast) you will have 10 seconds after pressing the 'Learn' button to get in your XF and hold the garage button you want to use and pressing your garage door remote to teach the car.

This will work, but just incase let me know if it doesn't.