OK, don't bust me up too bad here, I dont actually own a sentra, but my girl does and she has no internet access. (and no clue about cars)

she wrecked her 01, tearing the lower A frame loose and crunching the hood, but not puncturing the radiator.

it got impounded.

the stupid sherrifs department lost the key.

she tried to take it to nissan, but they wouldn't touch it because there was too much body damage.

so she took it to an automotive lock smith.

now the lock smith has the key cut, but claims they can't program the key because "somebody took out the factory radio"

I highly doubt this, since the car started and ran after the radio was stolen, so if they supposedly grounded some accessory control modual that handled both functions, and the key modual lost the code for the key, then the car wouldn't have started after that.

my guess would be that durring the accident some piece of body work frayed a wire and grounded the key modual. (or maybe the airbag deployed, leaving it in "safe" mode)

I have no idea what computers control what on this vehicle. it could be as simple as that it's in some sort of "protect" "vallete" or "safe" mode right now, and it might just need to be reset. would this be done by unhooking the battery, pressing the brake, and waiting 15 minutes? or would it need to be done at the dealer?

also, couldn't she just pick up another of whatever modual is malfunctioning off of e-bay and have the key coded to that one?

I'm unfortunately lost here, since this car is pretty new and not one that I'm familliar with, any help would be greately appriciated.