[hero3838]

Hi
I have issue a 2003 e53 x5 . We programmed a spare after market key after this car fob key both of key forgot ,car cranking and start without problem . If I initialize one key other key not working and also working one also not work after a few days but both of starting car . Ews3 no any errors
What is the problem ?

[foxportal]

replace the battery in the key.
you need to bind (initialize) two keys at the same time.