Telephone preparation uses Bluetooth radio technology to access your mobile phone. The system detects that your mobile phone is present in the car, and receives and uses all its SIM and GSM data. The system transfers all the relevant information to the car system using the remote SIM access profile (RSAP). This means that with just one SIM card all the directories stored in your mobile phone are also available in your car. The connection to the external aerial is made automatically, without you having to take the mobile out of your pocket or operate it.