I was just working on a 1999 Ford Mustang tonight and under "service" then "body" then "security" there was the option to enable and disable this feature (after waiting the 10 minutes to get through security). It was in the same location where you would program new keys.  I have seen this on other years of fords but off the top of my head I'm not sure what years I've seen it on. Unfortunately on this car I was unable to actually program new keys for some reason.  I've never had a problem programming Ford keys with my Maxisys before. I tried both a factory Strattec key and an aftermarket cheapo with no luck.

the maxisys said it could not communicate with module when I tried to program the key.  It logged into security fine and everything acted like it was working until actually programming the key.  At first I blamed it on the cheapo key he brought me, but then I tried a factory key and got the same problem.  I attempted with the original key and it said it was already programmed (so obviously it is communicating with the PATS module).  I did not try resetting the cluster and never found a solution on this one.  the one original pats key worked fine and there where no fault codes.  I did this guys 2001 ford f150 a few weeks before with no problems..