BMW X7 Overheating: Radiator Fan Failure Warning Signs

Hey there! I have some experience working on cars and had a similar issue with my 2021 BMW X5 last summer (I also owned an X3 before). The symptoms you're describing sound familiar, I had the exact same problems. In my case, it turned out to be a faulty speed sensor which was messing with the cooling system. The workshop diagnosed it pretty quickly after running some tests. The repair, including parts and labor, cost me around 250 Euro. Since then, everything's been running perfectly. Before I share more specific details about my repair experience, could you share: Have you noticed any other warning lights? Does the issue happen more during idle or while driving? Have you checked your coolant levels? Feel free to share more details so I can help better based on my experience.

Thanks for the detailed response! I've got 151396 KM on my X7, and yes, I've noticed it happens more when idling, especially after my latest service. No other warning lights besides the check engine light. Coolant levels are good, I actually checked those first thing. Your speed sensor situation sounds pretty similar to what I'm experiencing. Did you notice if your fan would occasionally work, or was it completely dead? Mine seems to kick in out of nowhere, which is what's throwing me off.

Hey again! Thanks for those extra details, it's helping me connect the dots with what I experienced. Yeah, my fan behavior was exactly like yours, super inconsistent. It would out of nowhere kick in, which actually made it harder to diagnose at first. I remember being parked at a drive-through and hearing it suddenly start working, then nothing for hours. The sporadic fan operation was definitely one of the most frustrating parts. Given what you're saying about the idle situation and the mileage, I'm even more convinced it's the speed sensor like I had. My X5 was showing the exact same symptoms around the 145,000 KM mark. The unusual fan behavior is a classic sign, it's basically the sensor sending incorrect signals to the ECU. Quick tip from my experience, while you're waiting to get it checked out, try to avoid sitting in traffic or long idles if you can. I found that keeping the car moving helped manage the temperature better until I got it fixed. Would you mind letting me know what the repair shop finds? I'm curious if it turns out to be the same issue. If it is the sensor, the fix is pretty straightforward and not too expensive, like I mentioned before.

Thanks so much for all this info, it's super helpful! You've actually made me feel a lot better about the whole situation. The similarities between your experience and mine are uncanny, especially with that unusual fan behavior. I've already called my regular mechanic and booked it in for tomorrow morning. I'll definitely avoid heavy traffic situations until then, appreciate that tip! I've got a good feeling it's going to be that speed sensor you mentioned, especially since our symptoms match up so well. The cost you mentioned sounds way better than what I was imagining, I was worried it might be something major with the cooling system. I'll definitely keep you posted about what they find. Thanks again for taking the time to share your experience, it's really helped point me in the right direction and calmed my nerves about this whole situation!