Just found out that for the keyless entry system on my 2003 Ford Expedition have a factory assigned code that cannot be deleted.You can personalize a different code but the original can still override.So by buying a used vehicle ,even a reconditioned unit how many people have had access to that code that cannot be changed.Especially finding out the owners manual with the key code card in it is missing.Hard for me to beleive in this world of codes and passwords that this has been going on and how many brands are effected.
I assume you are talking about the number pad on the door or many Ford products. That design was a Ford system, so it is limited to Ford, Lincoln, and Mercury. Factory software is needed to access those codes. Even if they have that code, the car isn't going anywhere - the keys all have individual chips that are programed to the car.
〉 Answered on Jan 2nd, 2014 by Helaine Kurot, Owner/Technician at 360 Automotive