BMW X3 Temperature Sensor Issues, The Complete Fix

Hey there! I had a similar issue with my 2021 BMW X1 last summer (I have some experience working on cars but nothing too advanced). The symptoms were exactly like what you're describing, temp display wasn't working, AC issues, and problems with heated functions. Took it to my regular workshop and they found it was just a loose connection in the wiring harness for the temperature sensor. Apparently, some cables had worked themselves loose over time. The fix wasn't too complicated, they had to reconnect and secure the wiring properly. Cost me about 95 Euro, including labor. Could you share more details about your X3? Like when did these issues start appearing? Did it happen suddenly or gradually? Also, what's the error code you're getting? This would help me understand if you're dealing with the exact same problem I had with my X1. BTW, I know BMW later addressed this in newer X models, but connection issues can still pop up. Let me know those details and I might be able to help more!

Thanks for sharing your experience! My X3 is fairly new with only 42635 KM on the clock, and just had its service last month. The issues actually started quite suddenly, I was driving home from work when the temp display just went blank. By the next morning, the AC and other temp-related functions stopped working too. The error code I'm getting is P0073, which points to the ambient temperature sensor circuit. Your wiring harness situation sounds similar to what I might be dealing with. Did your mechanic have to remove any specific parts to access the connection point? I'm trying to get an idea of the repair complexity before I take it in.

Hey again! Thanks for those extra details. Since you mentioned the error code and mileage, I can definitely tell it's very similar to what I experienced with my X1. In my case, when they worked on the wiring harness, they had to remove the front bumper cover to get proper access to the sensor area, it's a bit tucked away. But honestly, it was a pretty straightforward job, took them about an hour and a half total. The P0073 code is exactly what I had too. What's interesting is that your symptoms appeared so suddenly, just like mine did. I remember driving to pick up some groceries when everything just went haywire. The fact that yours happened right after a service is a bit concerning though, maybe something got knocked loose during the maintenance work? I'd definitely recommend getting it checked soon. Since your X3 is newer than my X1 was when this happened, it should still be under warranty. Mine wasn't, hence the repair bill. The good news is that once they fixed the connection, everything worked perfectly again and I haven't had any issues since. Let me know what you find out when you get it looked at. I'm curious if it turns out to be the same problem!

Thanks so much for all that detailed info! It's really helpful to know that removing the front bumper cover was part of the repair process, definitely not something I'd want to tackle myself. You're right about the warranty; I just checked and this should be covered since I'm still within the 3-year period. You make a good point about the timing with the recent service. I'll definitely mention that when I take it in. I've already scheduled an appointment for next week at the dealership. The sudden failure does sound exactly like what you experienced, so I'm hoping it's just that loose connection issue. It's actually quite reassuring to hear that your fix was permanent and you haven't had any problems since. I'll make sure to update this thread once I get it sorted out. Really appreciate you taking the time to share your experience, it's given me a much better idea of what to expect when I take it in!