This is from this forum September, 2013 by ElSupreme. Don't know if it helps: ElSupreme, Sep 27, 2013 I am pretty sure all cars made now have to have an OBDII port. And they are required to be near the steering wheel. The one in the Model S is directly above the dead pedal, under the steering wheel, as shown in this picture.
That's the OBD2 "federally required" port that doesn't really do anything. I'm looking for the diag port that most Model S years seem to have under the screen behind the cubby
LIke the kick panels or side of the center screen? I haven't looked in either, but is it possible it is in one of those spots?
The side panels beside the cubby. On my 2014 S the diag connector was behind the cubby. On my 2016 X the diag connector was behind the right side panel. The cable is pretty short, and just hangs down from the bottom of the MCU. The video and pictures here may help. You can see the cable drops down from the right side. If it is not in the cubby, it can also be down the side. Tesla Model S and Model X (2015 or older) | FleetCarma