BMW iX3 AC Issues: Blower Dead & Bad AUC Sensor

Hi there! I have some experience with EVs and had a very similar issue with my 2021 BMW i4 (also looked at the iX before buying). The symptoms you're describing sound exactly like what I dealt with last month. My blower completely stopped, and there was this weird musty smell whenever I was idling. Took it to my workshop where they found a faulty cable connection to the AUC sensor. The plug had worked itself loose over time and was causing the sensor to malfunction. The fix was pretty straightforward, they reconnected and secured the cable properly, plus did a quick system reset. Cost me 95 Euro and solved both the smell and blower problems completely. Could you share how long you've had these symptoms and if you've noticed any other electrical quirks? Also, what's your current mileage? This might help pinpoint if it's the same issue I had.

Thanks for sharing your experience! I'm at 194035 KM and just had my service done last week, but this issue started about 3 days ago. Haven't noticed any other electrical problems, everything else seems to be working fine. The smell is pretty consistent though, especially when I'm not moving. Good to know it might just be a loose connection! I'll definitely get the sensor connection checked out first before looking into more complex issues. Did your workshop need to order any special parts, or was it just the reconnection that fixed everything?

Hey again! Yep, in my case with the i4, it was really just the reconnection that did the trick, no parts needed. Though I should mention, after sharing my initial experience, I actually had the issue come back briefly about a week later. Turned out there was some corrosion on the connector pins that they hadn't spotted the first time. Had to go back to the workshop and they cleaned the connector properly with some electrical contact cleaner, that's what really solved it for good. Given your higher mileage (mine was only at 85000 km when this happened), I'd definitely suggest asking them to check for corrosion too, not just the loose connection. The fact that your issue started so suddenly after a service is interesting though. Maybe they accidentally knocked something loose during the maintenance? My technician mentioned these sensors can be a bit finicky if they're disturbed during other work. Either way, it's usually a pretty quick fix, I was in and out in about an hour the second time. Let me know how it goes with yours, curious to see if it's the same root cause!

Thanks for all that detailed info! You're probably right about something getting knocked loose during the service, the timing does seem pretty suspicious. I'll definitely mention both the connection and potential corrosion when I take it in. Really hoping it's as straightforward as your fix was! Just booked an appointment for tomorrow morning, since I'd rather get this sorted sooner rather than later. The smell is getting pretty annoying, especially with this traffic lately. I'll update everyone once I find out what the actual issue is. Thanks again for sharing your experience with the i4, it's super helpful to know what to expect and what to ask them to check specifically!