7-Way Trailer Wiring Harness Stopped Working on 2012 Q7
 

Hi All,

I have a 2012 Audi Q7. I had the Audi dealer install a 7-way wiring harness on the factory installed lead. After installing a Tekonsha Prodigy RF break controller everything worked fine (...once I discovered the trick to pair the RF controller!) for 1-1/2 years and about 8 long distance trips.

Then 2 trips ago I started to get a "Replace Back Left Trailer Light" error message. The left blinker indeed did not work. Then the next trip all the the trailer lights failed (blinkers, break, running, etc.) and the Q7 is not acknowledging that it's connected to a 7-way at all. (The auxiliary towing blinker indicators don't come on when the blinker is used.)

The Audi techs are at a loss saying they have "run all the codes", have "checked the module", "checked that the software is updated", and they even loosened the 7-Way adapter to show me that the leads to it were still attached and in good shape.

Lastly, I bought a Tekonsha 6562 7-Way Blade Tester and Trailer Emulator with LED Display and brought it down to the shop as I felt a "Are you sure it's not your trailer?" -- denial coming on.

*** Sure enough, when plugged directly into the 7-way on the Q7 the top three LED lights (marked LT, TL, & RT) flutter rapidly instead of lighting solid or responding to blinker, break, or the car being put into reverse. ***

Has anyone at heard of anything similar? Any advise on what the Audi tech's should do next?

I am looking for any leads as this has so far stumped Audi's technicians for three days.

[Oh, and I did have the trailer tested... the lights work fine with a tester that the RV mechanic had that was designed for a 7-way.]

Thanks in advance if you've ever heard a similar tale!
-Rob