BMW 6 Series Climate Control & Error Messages Puzzle

Hi there! I've got some experience working on BMWs and had a similar issue with my 2001 BMW 5 Series (had a 525i back then, now driving a 3 Series). The symptoms you're describing sound exactly like what I dealt with. Initially thought it was just a sensor, but it turned out the AC control unit itself was fried. The error messages and complete AC failure were identical to your case. Took it to my regular workshop, and they diagnosed it after running some tests. Had to replace the entire AC control module, wasn't cheap at 980 Euro, but it fixed all the issues completely. The error messages disappeared, and climate control started working normally again. Could you share which 6 Series model you have specifically? Also, are you getting any specific error codes? This would help me give you more detailed insights based on my experience. Side note: These control units can fail pretty often in BMWs from that era, so it's actually a somewhat common issue.

Thanks for your input! Mine's a 630i with 198971 KM on the clock. Got similar quotes for the control module actually, but I wanted to make sure before dropping that kind of money on it. Haven't noticed any specific error codes other than the general system failure message. Was the replacement job pretty straightforward in your case? Just wondering if there's any other potential issues I should check before committing to the module replacement. The symptoms are almost identical to what you described, so that's definitely reassuring to hear.

Hey again! Yeah, I totally get your concern about the cost, I was hesitant too before replacing my control module. Since we're dealing with similar BMW models, I can tell you the replacement job itself was pretty straightforward. The workshop had it done in about 2-3 hours. Just to be extra sure though, I had them check the wiring harness and connections before going ahead with the module replacement. In my case, everything else was fine, but it's worth checking since these cars can develop wiring issues over time. The mileage on your 630i is pretty similar to what mine had when the problem occurred (I was around 190,000 KM). One thing I remembered, after they installed the new module, they had to do some basic programming to make it communicate properly with the car's systems. Make sure wherever you get it done can handle that part too. I've had zero AC issues since the replacement (it's been about 2 years now), so while it wasn't cheap, it was definitely worth it in my case. Given how similar our symptoms are, I'm pretty confident you're looking at the same fix. Just double-check about the programming part, that's crucial for these BMWs.

Thanks so much for all the detailed info, this is exactly what I needed to know! Really helpful about the programming part, I wouldn't have thought to ask about that specifically. Think I'll go ahead and book it in with my regular workshop next week, they've worked on plenty of BMWs so they should be able to handle the programming too. Actually feeling quite relieved now knowing this is a common issue with a clear fix, even if it's going to hurt the wallet a bit! Will make sure they check the wiring harness as well before proceeding with the module replacement. Really appreciate you taking the time to share your experience, definitely helped me make up my mind about how to proceed with this. Cheers for the help!