alright I got this from http://www.bimmerfest.com/wiki
1. Get in and close all doors.
2. Turn on the ingition and turn off quickly. (No more than 5 seconds) to start the process. Next action must take place within 30 seconds.
Here is my question... turn on the ingition means start the engine?
3. Remove the 1st key.
4. Hold the key up near your left shoulder (this is so it is closer to the remote reciever antenna - someone else suggested this).
5. Hold down the unlock button (which is button 1 on my key) and press the lock button 3 times (center button on my key). Release the unlock button and the doors lock which confirms the operation.
6. Quickly repeat steps 4 & 5 for key #2 etc.
If it does not work, try doing the keys in opposite order.
Key 2 then key1, vs 1 then 2.
Remember to alternate your keys from time to time so that you keep the batteries in both charged.