Aggie88

I need some real world experience from one who has towed with their Q7 with a factory system. I have installed the lighting connector and purchased a 4 wire adapter to connect to a Uhaul car trailer. But when I test it with a probe, there is no voltage at the terminals. I recall a thread where it was mentioned you have to get a special connector from Audi. What is that part?

Jusforfun

Possibly when you connect up the car will recognize the draw and kick it in. It prolly needs the resistance of the bulbs. When I plug in (EU spec) it does a quick check and puts trailer left tail lamp failure on the screen and beeeeeeeeps at me.
BTW it also knocks off the reversing sensors and automatically goes into towing mode.
It seems to be able to detect the trailer despite them being off as it shows a caravan until I engage reverse when it changes the pic to a boat as there is nothing at the outer sensors.

I think the special connector you mention was for electric trailer brakes.<ul><li><a href="http://www.etrailer.com/pc-A~37358.htm">http://www.etrailer.com/pc-A~37358.htm</a</li></ul>