Trailer Wiring

[menjohnson]

I was recently doing research on this subect and thought I'd post what I learned/did. For those of you who did NOT install the VW OEM hitch and wiring and plan on after market, read on, if you like.

People have reported problems with after market wiring converters giving MFI bulb failure messages, light outages, etc... This is because the vehicle senses the additional amp draw of the trailer lights, (it's probably seen as a ground fault, not exactly sure, doesn't really matter.)

I used a Hoppy 46365, this is a universal power converter. Hoppy hasn't designed a Plug-In-Simple for the Tourareg, so you must wire tap into the various lights, hence the "Universal". This unit being a power converter however, solves the problem of the additional amp draw sensed on the vehicle lights. The power converter has it's own power source, so the input from the vehicle lights become simply signals for the power converter, it in turn powers the the trailer lights, and the operation is invisible the the vehicle.

The power converter instructions call for you to run a power lead directly to your battery, not necessary since the Touareg has power outlets in the right wheel well which are always hot and 20 amp circuits. Simply tap into one of the power outlets, they are of adequate amperage and your power converter will be housed in this same wheel well.

If you don't want to tap into your wiring then go with the factory set-up. This set-up will NOT communicate with the Touareg computer. This was a plus for me as I did not want the computer doing the behind the scenes changes when I plugged the trailer in.

You can probably order this power converter shortly from treg central, I was communicating with them as to whether it worked, and I am happy to report it works as advertised.

Hope this helps, I'll update if I run into any problems down the road.