Got this from another forum
"For my MINI I used a "Powered" plug that "protects your car's computer from the trailer"
Lots of manufacturers make them, Hoppy, Uhaul, etc. The key is to use a plug that has its own battery connection.
Here is information on How I did the MINI. Ignore the MINI specific color codes and read the information below the table.
http://user.mc.net/~jdewey/MINI/Trai...ng_color_codes...
John.
Eagerly awaitng my Smart."