theshipper

Hi all - New member and first post but longtime reader. My 2015 A6 3.0T (C7) has a funny issue: The center console 12v outlet and rear passenger 12v outlets (2x) will only operate and provide power when the headlights are switched to full on, or at times in full darkness when the automatic headlight setting (the headlight dash switch) automatically turns the headlights on. So, (1) if the headlights are on auto but its daylight, the 12v outlets do not work and do not provide power; and/or (2) when I have the headlights switched to the full 'off' position the 12v outlets do not work and do not provide power. I checked the fuse and relay and they appear to be fine. I went as far as swapping in a new functional fuse into the 12v fuse location to confirm and it is the same result. Whenever the 12v outlets are working and provide power, the red light ring around them lights up; and when the 12v outlets are not working and not providing power, the red light ring around them does not light up. I read on a different forum (related to fiats?) that it is possible that there is a ground issue where the 12v outlets are not able to ground properly until the headlights are turned on which may be cuasing this effect (like a short or bad ground?), and when the headlights are activated then the 12v outlets are able to piggyback and find a ground via the headlights and then operate normally. I found that tidbit here: https://xwebforums.com/forum/index.php?threads/cigarette-lighter-headlights-do-not-work-at-the-same-time.12915/ Is this a thing with Audis or has anyone ever heard of it before? The problem I have is basically an annoyance (like if I need the 12v I just make sure the headlights are actually full on) but I wonder if it is a symptom of a larger problem which can become a bigger deal over time. The car has been this way for at least 3-4 years but that's when I first noticed it, it may have been this way since it came off the factory floor. It certainly doesn't seem like it is intended to operate normally this way. It is a 2015 model which I bought CPO in early 2018 with about 23k miles and no acidents/clean carfax. The only known incident with the car is a driver side door ding which was fixed prior to purchase, and you can see the paint on the forward edge of the driver door and rear edge of the front fender adjoining it was refinished in connection with that. I mention this last bit above but because I wonder, if the theory about a bad ground is valid, then maybe the relevant ground location for the 12v outlets is in that area of the door and it was messed up when they fixed the door ding/refinished the paint? I think that fender was re-fitted to the body (I believe that to be the case because they didn't do it perfect and I don't think it would be like that from the factory) and wonder whether the ground would be under there and could be the root cause - That is, if the ground theory above holds any water. I started trying to figure out what ground relates to the actual 12v outlets to check whether this is the root cause but I'm hopelessly in over my head in trying to figure that out myself via google and looking at audi wiring diagrams, it seems like there are about a thousand possible ground/fault locations. This is a long post so thanks for reading and for any help anyone can provide. Thank you!