hey there im new here and ill be buying my self a truck in a few days yes a ford.
now i have a question ive noticed on the ford keys for the newer models 2008 and up they have s and sa stamped into them and was wondering what the difference is between the two keys
Thanks

 

Its Encryption. S keys are Ford old PATS (passive aint-theft system) 40 bit encryption, the newer SA is an 80 bit encrytion that is backward compatible with old PATS using cars. Hope this answered your question.

 

Ford has went to "chipping" their keys? I know GM dabbled with it in the late 90's early and had some issues. We had to clean the contacts on the key with a pencil eraser. The chips were nothing more than resistors the computer read. If it didn't read the correct resistance programmed for that car it wouldn't work.

 

Ford has used a PATS system for their vehicles starting in the late 90's/early 2000's, although the Super Duty didn't get PATS until 08+. The Ford system is much more reliable than GM's early endeavors.

 

In Canada the CMVSS requires all cars 2007 model year or newer to have some form of immobilizer... many automakers went with some variant of a RFID device. This is a non contact system so there won't be issues with dirty electrical contacts. It's like those keyfobs or ID cards to get into a commercial building / multi dwelling unit or those contactless smartcards to log on to your computer.

 

I know what you're talking about. It's called Passive Keyless Entry. It uses a small rfid or similar device to activate a lock etc without physical contact. Pretty cool stuff. You can buy kits to add that to your home or car.

Keyless Ignition RFID Push Button Start systems

 

To give a bit more history, the first cars equipt with PATS (Passive anti theft system) was the 1996 Taurus. From then on Ford has added it to to just about every car.

 

I have been a ford tech for 30 years and SA keys are NOT backwards compatible with S keys regardless of what Ford says.