I have seen quite a few posts from people who purchase used tuners from EBAY or other sources, when you buy from other sources other than licenced dealers or directly from Diablo Sport you risk getting a married tool, this means the tool is set or married to a specific vehicle and will NOT work with any other vehicle until original vehicle is returned to it's stock tune. If you do buy a tuner and it isn't unmarried you are screwed! I don't think the tuner can be flashed to it's original unmarried state. If this is your situation you need to get in touch with seller to get them to unmarry your tuner. All I can say is GOOD LUCK, most seelers of used tools want nothing to do with your problem, most have sold or totaled their vehicles!
I know the some tuners can be unlocked but I don't think the Predator can, I have read quite a few posts from the DiabloSport forum posted by the DS tech guys that say "that's too bad, you have a big problem, see if you can get the seller to unlock it for you"!
if u do buy a used 1 just make sure it is not married to another car!!!!!!!!!!!
x2. thats what i did. He "unmarried" it right infront of my eyes, luckily, i wasn't aware of the possibilities at the time. Anyway lazor is correct. The DS predators CAN"T be reset if it is married to another car, must go back into that car and have the stock tuned reprogramed on there.