BMW X5 AC Failure: Compressor Issues & Warning Lights

Hey there! I've got some experience with car repairs (some experience level). I had a very similar issue with my 2011 BMW X3 3.0i last summer. Initially thought it was the compressor too, but turned out to be the AC control unit that was completely fried. The symptoms were exactly like yours, no cooling, system wouldn't engage, and warning lights popping up. Took it to my regular workshop and they diagnosed it properly after running some tests. The control unit replacement set me back about 980 Euro, but it fixed the problem completely. I also own a BMW X1, so I'm quite familiar with these models. Before jumping to conclusions, could you share: Are you getting any specific error codes? Does the fan blow at all, just not cold air? When did you last have the AC serviced? This could help narrow down if you're dealing with the same issue I had or something else entirely.

Thanks for sharing your experience! I'm having those exact same symptoms with my X5. The fan blows but no cold air at all. I had my last major service about 8 months ago at 146120 KM, but they didn't specifically check the AC system. I'm getting error code P0645, which from what I've read could indeed point to the control unit rather than the compressor itself. Really helpful to know that you had a similar experience, definitely gives me a better idea of what to expect and where to start looking. Might save me from unnecessarily replacing the compressor first. I'll get it checked out at the shop this week. Will keep you posted on what they find!

Hey again! Thanks for the update, and I'm glad my experience with the control unit issue was helpful. That P0645 code on your X5 is exactly what I got on my X3 too! It's actually really interesting because when I first saw that code, I was also convinced it was the compressor, just like you. Having gone through this myself, I can tell you that the control unit is looking more and more likely here. Just a heads up, when they replaced my control unit, they also recommended doing a full AC system check and recharge. I went ahead with it since they had to evacuate the system anyway. Whole thing took about 4 hours in the shop, but it's been running perfectly since then. One thing I learned from my experience, if they do confirm it's the control unit, make sure they check the wiring harness too. My mechanic found some corroded connections while doing the replacement, and fixing those probably prevented future issues. Definitely keep us posted on what they find! Really curious to know if it turns out to be the same problem. These BMWs can be tricky sometimes, but at least when you find the right fix, they run like a dream again.

Thanks a lot for that detailed follow-up! You've basically confirmed what I was starting to suspect. It's really reassuring to hear that fixing the control unit solved the exact same issue for you. I'll definitely ask them to check the wiring harness too, hadn't thought about that potential problem. Good call on the full AC check and recharge recommendation as well. Makes sense to do it all while they're in there anyway. I've already scheduled an appointment at my local shop for tomorrow morning. After hearing about your experience, I'm feeling much more confident about what to expect and what to ask them to check. Really hoping it's just the control unit and not something more serious. I appreciate you taking the time to share all these details. When everything's fixed, I'll make sure to update the thread so it might help other BMW owners dealing with similar AC issues in the future!