There's every chance that the radio will need re-coding, 99.9% sure.
There should be a record of this in the service book or even in the destructions for the stereo, could be hand written or a sticker, so have a good look before you disconnect it, failing that, if its the original Jeep item, a phone call to your local stealership with the reg number & Chassis number on hand, they should be able to tell you ;)