BMW 8 Diesel Climate Control System Complete Failure

Hey there! I've got some experience with BMWs and had a similar issue with my 2016 BMW 6 Series Diesel. The symptoms were almost identical to what you're describing. Took it to my regular workshop and turns out it was a faulty wiring connection to the ambient temperature sensor. The connector had corroded over time, causing all those weird temperature-related issues. The fix wasn't too complex, they replaced the connector and rewired it properly. Cost me around 95 Euro and everything's been working perfectly since then. Before diving in too deep though, could you share which error code you're getting? Also, have you noticed if these issues started suddenly or gradually? This info would help determine if you're dealing with the same problem I had. If you want, I can recommend what worked for me until I got it fixed (though my experience is somewhat limited to this specific issue with BMWs). P.S. The 8 Series is sweet! I actually considered getting one before going with the 6.

I had my latest service about 3 weeks ago at 142671 KM, and sure enough, same symptoms popped up just after. The error code I'm getting is P0073 (Ambient Air Temperature Sensor Circuit High). The issues started pretty suddenly, right after a heavy rain actually. The connector corrosion you mentioned makes a lot of sense given the timing. Did your mechanic mention if this is a common issue? Just wondering if I should expect this to happen again after getting it fixed. Also, I'd definitely appreciate any temporary fixes you used, I've got a few long drives coming up and want to be prepared just in case. And thanks for the kind words about the 8 Series! Really love it apart from this little problem.

Hey again! Thanks for following up about your 8 Series. Actually, that's exactly what happened with my 6er, issues showed up right after some nasty weather. That P0073 code is definitely familiar, it's the same one I got. My mechanic did mention this is pretty typical for these models, especially once they hit around 130,000-150,000 KM. The connectors aren't as weather-sealed as they should be, and water eventually finds its way in. Before I got mine fixed, I used a temporary fix that might help you out, I sprayed some electrical contact cleaner into the connector (after carefully disconnecting it), then used some dielectric grease to help keep moisture out. It worked as a band-aid solution for about two weeks until I could get it properly fixed. Just a heads up though, after my repair, my mechanic applied some extra sealant around the new connector to prevent future issues. Might be worth asking your mechanic to do the same. I haven't had any problems since then, and it's been about 18 months. Honestly, considering your symptoms started after rain and you've got the same error code, I'd bet good money you're dealing with the same issue I had. Let me know how it goes when you get it checked out!

Thanks so much for all the detailed info! That temporary fix with the electrical contact cleaner and dielectric grease sounds like a smart solution, I'll definitely give that a try until I can get it to the shop. Really appreciate you mentioning the extra sealant too, I'll make sure to ask my mechanic about that when I take it in. It's actually quite relieving to hear this is a known issue and not something more serious. Sounds like I caught it at the typical mileage too. I'll probably schedule an appointment next week to get it sorted properly. The fact that you haven't had any problems for 18 months after the fix is really encouraging. Really appreciate you taking the time to share your experience. It's saved me a lot of worry and probably some unnecessary diagnostic costs too. I'll update you once I get it fixed!