VW:connector:N91-10791:Media Device Interface (MDI) USB Specifications
http://www.my-gti.com/1287/volkswagen-media-device-interface-mdi-usb-specifications
Volkswagen Media Device Interface (MDI) USB Specifications
Overview of connectors on USB connection
1 – Data in, (here output)
2 – Data clock
3 – Voltage supply, terminal 31
4 – Data out (here input)
5 – Not assigned
6 – Voltage supply, terminal 30
7 – LF audio signal, right, positive
8 – Control line, positive, switched from radio
9 – LF audio signal, negative
10 – LF audio signal, left, positive
11 – Not assigned
12 – Not assigned
Overview of connectors on USB connection
1 – Data in, (here output)
2 – Data clock
3 – Voltage supply, terminal 31
4 – Data out (here input)
5 – Not assigned
6 – Voltage supply, terminal 30
7 – LF audio signal, right, positive
8 – Control line, positive, switched from radio
9 – LF audio signal, negative
10 – LF audio signal, left, positive
11 – Not assigned
12 – Not assigned