More Towbar Electic Woes

Car companies are doing everything possible to lower emissions. One thing they do is reduce battery drain for non essential circuits by turning them off until they are needed. Should they do this in this application, only they know. From what has been said in posts above they seem to be turning it off and only activating it with the other comfort features, common to do this in other applications on the vehicle but questionable on what is designated a permanent feed.

The fact is, nothing is drawn voltage wise from a permanent live till something is plugged in to it that uses power so why would it flatten a battery.   

Lornalou, there is no EU standard, law or otherwise for what is connected by the manufacturer in the factory, beyond the trailer lights. Many EU car manufacturers with factory fit tow-bars do not wire up the live feed. neither My 2006 A6 or 2013 Passat with factory towbars were wired for fridge and battery.  

You are correct in saying it is not an EU standard however ISO 11446 for 13 pin wiring is an international standard.

well we know from previous posts that the Germans don't like to do permenent lives from factory or dealers but most indipendants do it as a matter of course. A dedicated wiring kit give you this automatically in the loom.