Originally Posted by 1move

You need both of your switchblade keys to re-program them, you can program up to five switchblade keys:

Take the key you do not want to program (if it already works) and put it in the ignition. Turn it one click forward.

Close and lock the drivers door with the second key with the window down (you can also do this from the inside of your car).

On the second key (the one in the drivers door) press the 'UNLOCK' button ONCE only, the lights will flash on the car, but the doors will remain locked

With the second key still in the drivers door, unlock then lock the door again.

Pull the key from the slot and also take out the key out of your ignition and than test the remote functions.

Repeat for second key fob / switchblade / key whatever you want to call it !!! Enjoy!! This worked on my 04 a4 1.8t !!

You might end up doing it a few times to get the hang of the procedure so its all a smooth one step type of thing and the comp will learn it! NOTICE if you are too slow / too fast this will not work!!