Please double compare the adapter interface with your car original port mount,when the function is not working, please try to restart your cell phone, that will help
Plug the adapter into the media interface port in your car and pair it with your Android, iPhone, iPad or iPod touch via Bluetooth
For bluetooth mode, you could only change songs from the smartphone, can not control over music from the iDrive system , the playlist will not be displayed on the car screen
For USB mode, you could charge your device, or use the USB function to listen music (listen music: the Disk must be FAT32 format and *.mp3 file , notice that few MMI system don't support USB function)
Compatibility: Mercedes A (Not A4) /B/C/E/S/GL/ML/SL/CLS/SLK Class (From 2009 ~ Onwards)