Most BMW vehicles come from the factory with a radio that has a anti-theft radio code. The code is only required when the radio is taken out of the car or if the battery dies or is disconnected. Many times, BMW owners will forget their unlock code for the radio or will have never had it if buying the car used. A third party service can be used to retrieve the unlock code. Most services will require you to send the car stereo’s serial number.
Insert your car key into the ignition, leaving it in the “off” position.
Depress and hold the “M” button on your radio.