I seem to have the same troubles as described here: Problem connecting Fairphone 2 to PC (the part about data connection).
Most of my USB cables actually seem to be only-charge cables.
But I do have two data cables, and they do work for another android phone as data cable.
For this Fairphone2, they don’t even work properly for charging. When I attach the FP2 to a PC, it will show the charging state for about 1-2 seconds (and the charging LED will light up for the same time), and then both the charging indication in the status bar stops and the LED goes out. Neither is there any notification about connection options as with the other android phone.
TL;DR: Enabling USB debugging and disabling it again (while phone was connected to PC) fixed it for me! See also last post.
Anybody else had issues like that before?
As I have another bottom module available, I’ll try my luck with that one, maybe there is some connection issue…