BMW 7 Hybrid Mirror Issues: Heating and Dimming Problems

Hey there! I have some experience working on cars, and I actually faced a similar issue with my 2017 BMW 5 Series Hybrid (also own a BMW 3 Series). The mirror heating and dimming problems can be super annoying, right? In my case, it turned out to be a faulty cable connection at the mirror assembly. Took it to my regular workshop, and they found that moisture had gotten into the connection, causing intermittent issues with both functions. They had to replace some wiring and reseal the connection properly. The whole thing cost me around 95 Euro, but it's been working perfectly since then. Could you share what error code you're getting? Also, does the problem occur on both mirrors or just one side? This would help me give you more specific advice based on my experience.

Thanks for sharing your experience! My issues are actually showing up on both mirrors. The error code I'm getting is E4F-76B3 (got it from my OBD scanner). Just had my service done at 173121 KM, so I'm a bit bummed these issues are popping up now. Really appreciate the tip about checking the cable connections, I noticed some slight discoloration around the mirror housing, which might indicate moisture damage like you mentioned. Did you notice any obvious signs of water damage before you got yours fixed?

Hey again! Thanks for the follow-up and sharing those details. Yes, I totally get your frustration about issues popping up right after service, that's never fun! Actually, when I had my mirror problems, I did notice some similar discoloration on my BMW 5 Series. It wasn't super obvious at first, but there was this slight whitish residue around the mirror housing edges. Looking back, that was definitely a telltale sign of moisture getting where it shouldn't be. That error code you're getting (E4F-76B3) is really similar to what I had. Since you're having trouble with both mirrors, it might be worth checking the main wiring harness that connects to both sides. In my case, even though the visible damage was mainly on one side, moisture had traveled through the harness and affected both mirrors. Quick question, have you noticed if the problems get worse in damp weather? With mine, the dimming function would go completely crazy after rain or car washes. If you're experiencing something similar, I'd bet money it's the same moisture issue I dealt with. Just make sure whoever looks at it checks the entire wiring path, not just the mirror units themselves. That was key in fixing mine permanently rather than just patching up the obvious damage.

Thanks so much for all that detailed info! You've actually hit the nail on the head about the weather, I've definitely noticed the dimming goes completely wonky after it rains or when it's really humid. Didn't make the connection before, but now it makes total sense. The discoloration I'm seeing matches exactly what you described too, that whitish residue around the edges. I'll get it checked out this week and make sure they inspect the whole wiring harness like you suggested. Really don't want to end up with a temporary fix that'll just cause problems again later. You've saved me a lot of troubleshooting headaches here. Will let you know what they find when I get it sorted. Really appreciate you taking the time to share your experience!