4.2. General description

The following control units act as the interface between the mobile phone and the vehicle:

The preconditions under which TCU or TCU and interface box together are installed are listed below:

COMPONENTS DESCRIPTION CHART

Optional extra	Installed control units
Complete basic fittings for mobile phone (option 639)	TCU
Complete basic fittings for mobile phone (option 639) + USB audio interface (optional 6FL)	TCU ULF-SBX High
Complete basic fittings for mobile phone (option 639)+ Smartphone Integration (option 6NF) + USB audio interface (option 6FL)	TCU ULF-SBX High (Base plate and cradle for Smartphone integration

NOTE: The ULF-SBX High is only used for the USB Audio Interface (option 6FL), the TCU is used for all other telephone and BMW Assist functions.