Q&A

 Master

This means that the power to your radio was lost, was your battery dead?
When the power is lost to the radio, you need to enter a code to make the radio work, this is for security reasons, to help prevent theft.

 Enthusiast

http://www.bimmerfest.com/forums/showthread.php?t=106564

you need the radio code. don't know why your car won't start tho.