Good morning Ray,
We have a 2010 Roadster and a couple of years ago had the management light illuminate, I got a very similar unit to the one in your post from EBay, plugged it in, followed the instructions and cleared the fault, strange thing is I have never used it since.
It now resides in the passengers footlocker, just in case, I found the connection lead tucked under the left hand side of the dash on the drivers side.
Good luck
