I got a second hand tuner from my grandpa and when I plug it in it says it has already been used and turns off...this doesnt make any sense. is it one car registry?

 

The answer is painfully obvious to even the most casual observer.

Yes, it's locked.

BTW, thanks for all the information. It makes helping you soooooo much easier.
programmer brand
programmer model number
vehicle it came off of
-make
-model
-year
-engine
your vehicle
-make (Ford?)
-model (F150?)
-year (97?)
-engine (4.2, 4.6, 5.4?)
-transmission

Have a nice day!

 

here we go again