I bought another key from the dealership and had it cut there to, but when I tried to use that new key on my nissan the car won't start.

ANY SUGGESTIONS

Does it go in all the way and can you turn it?
The steering wheel might have locked up try to loosen it a bit and then try to start the car ;)

The key needs to be programed to your car. It is an anti-theft system called NATS. Take it and your car back to the dealer and have them program it. Make sure you take all of your keys with you because if they need to program all of them together.

Cant you program your key yourself? I'm pretty sure it's nothing but cycling the key in your steering column and you also need 2 already programmed keys. Is this right? Perhaps he can find a tutorial online somewhere or one of you guys might know it. Might be expensive to program it at the dealer.

I just bought a keyfob off the web. It should be here today they are sending the programing instructions with it. Counldn't I use that and program the new key.:D

Programing keys is different than key fobs. You can do the key fob yourself. Get in the car. Lock all doors. Push the key in and out untill the hazards flash (about 7 times in and out). After they flash put the key in and turn on but do not start the car. Push a button on the key fob. If you did it right the hazards will flash and you're done. Check to make sure all the functions work.

You have to take the key to the dealer to get it programed. There is a code we have to get from the BCM and enter it into a database to get another code. Depending on what your dealer's shop rate is it's .5 hour labor. So if your dealer is $100 an hour it will cost $50.

Got the key fob programed.

Is the panic button a alarm or just a button because when I lock my doors and the horn beeps then put my arm over the window and unlock the door nothing happens.

The panic button is for when you are getting attacked by your car you can hit that button and the horn will start honking or if you can't find your car in a parking lot. Not sure what you mean by "puy my arm over the window and unlock the door nothing happens".

Putting my arm over the window if someone was trying to break into my car, and my window was halfway down. If they unlocked the door would anything happen.

Nothing would happen.