Unlimited Key Mode
WARNING: This page is about a different car, the 2010 Lincoln MKX and 2010 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.
PATS contains a feature called unlimited key mode and uses the UNL_KEY_MODE PID. This feature allows a customer to program more than 8 keys to their vehicle if they request it. Each vehicle in unlimited key mode is set up with a special unlimited transponder security key code. This allows all the customer vehicles to share the same mechanically cut keys, but no other keys from outside can be used to operate the vehicles. For an individual customer, any security key that has been previously mechanically cut and electronically programmed to the vehicle is acceptable.