Giblet

It is a well-known fact that the early '07 models did not have the pre-wiring for the trailer brakes until VIN _7D015246+. This of course was a huge oversight by Audi and there have been reports that Audi was planning on retrofitting the missing harness for those affected who wanted to use electric brakes.

My question today is has anyone actually successfully had Audi do this under warranty/goodwill? If so, please respond with your experience. If not and you went a different route with an aftermarket/non-OEM solution, what was it?

I currently have the non-factory hitch setup with the EBC installed in the rear. I have hooked up the trailer lighting harness but since my VIN is in the affected range, do not have the trailer brake harness to plug into the back.

gazman

my car is an 06 build 3.0tdi. It was pre-wired, so connecting the trailer brakes was straight forward. Have you checked in the drivers side footwell, removing the plastic panel, there may be a plug, covered in grey foam. If so, this it the plug for the trailer brake unit. I use a Prodigy, which plugged right in. Now in the boot, next to spare, this pre wired cable terminates with another foam covered plug. Let me know if you have these, and I will advise further.

Giblet

Based on your vehicle being a TDI, I reckon that your's is European Spec. The US Spec vehicles seemed to have excluded this wire (and yet I have the Euro hitch in my vehicle which is useless).

I did check for the wiring and it wasn't there. Took it to the dealer to make sure I wasn't just missing it and they confirmed as well (based on the TSB) that it wasn't there.

I do have a happy ending to this story though as I will be taking it in next week to have the wiring added (courtesy of Audi). So for all those missing this piece - there's your precedence. I will be talking to the tech to understand how much of the car will need to be in the path of the wiring to ensure that I don't have any new rattles and squeaks as a result but this does make the Q7 safely able to pull up to its advertised 5500 pounds.

Giblet

Well, she's back in the driveway after having open interior surgery. So far, everything looks like it made it back safely.

I did notice some rear seat whole covers were removed. One was not put back properly and the other must have broken while being removed. The two pieces (which snap together) were loosely held together with some sticky resin.

nette

Hi Giblet, I just saw your post and was hoping you could help me. I have a 2007 Q7 with the factory installed tow package, but it is NOT pre-wired. I found that out after I purchased a beautiful 23 foot Airstream that now sits in our driveway since several weeks.

I took the Audi to the dealer, they warned me that they had never re-wired a Q7 before. Fortunately I did not have to pay for it (except of the electronic brake controller they installed at the same time). 10 long days later I had my car back, hooked it up to the Airstream and it did NOT work... the tail lights on the trailer keep blinking and on my dashbord I get a notification that my trailer light is not working. The brake controller seems to be connected since I see a green light. After talking to Audi they hinted that they were not sure what the problem is...

A very helpful person on the Airstream Forum suggested a 7-Way to 7-Way Trailer Adapter. Did you need to add that to your Audi to make it work?

Giblet

Hi nette,

Sorry to hear of your complications. Seems like during the surgery the patient developed an infection.

I was fortunate to not have any issues as my dash seems to show everything working properly. I ordered the exact Brake Controller that Audi recommended (a Valley Odyssey model) and mine fortunately worked right out of the service bay. I am pulling a very large Coleman tent trailer with the standard wiring it came with and have had no issues to date.

I believe I did read somewhere that the Brake Controller needs to be a verified compatible model. I have a faint recollection that some Prodigy models where problemmatic due to the constant low current trickle that Audi is using.

Hopefully Audi plugged everything in to the electronic brake controller unit (that sits in the back) correctly. I also hope they didn't forget to code the car for the brake controller. Other than that, I am not the right person for troubleshooting this as this is the first vehicle where I have towed a trailer.

Thanks for confirming that you also had Audi retrofit the wiring in your vehicle. Good to hear that they are taking responsibility.

emzet

Hello Gilbert. I just saw your post and noticed that you "have hooked up the trailer lighting harness" yourself. Can you remember what harness you have installed and how you have done you installation? I am after installing the Curt hitch onmy 2007 Q7 and trying to find out how to install the ellectrical connection. Specifically:
- what harness to use?
- how to find the wires to which I should hook up the electric harness (where are they located, how do they look like)?

Any help from you or anyone who has done this is greatly appreatiated. Btw, I do not need the brake controller, just connecting the lights to the trailer.

Thanks

emzet

Giblet, I am very sorry for misspelling you name my previous post. My humble apologies

emzet

Can anyone comment on my question above, please? Thank you in advance

dukesean

Check this https://www.audiworld.com/forums/sho...ight=tow+hitch

Or find other thread start by giblet

Good luck