BMW X3 Climate Control Dead: Temp Sensor or More?

Hey there! I have some experience working on cars, and I actually faced a similar issue with my 2006 BMW X5 3.0i. When I first noticed the climate control acting up, I thought it was the temp sensor too. Took it to my regular workshop and turns out it was actually a loose connection in the wiring harness connected to the climate control module. The mechanic found that some cables had worked themselves loose over time. Total repair was 95 Euro, mostly labor costs for diagnosing and fixing the connection. I've also owned a BMW 5 Series, and these electrical gremlins can be tricky to diagnose without proper diagnostic tools. Could you share if you're getting any specific error codes? Also, does the fan still work at all, or is it completely dead? This info would help narrow down if you're dealing with the same issue I had.

Thanks for sharing your experience! My X3 has 96010 KM on the clock, and the fan actually works on manual mode, but nothing happens when I press the AUTO or AC buttons. The error code I'm getting is "ECC" on the display panel. I was hoping it would be something simple like your wiring issue, but I'm starting to worry it might be more complex. The fan speed controls and temp adjustments are also becoming inconsistent. Did your loose connection cause intermittent operation before it failed completely? Just had my regular service done last month and everything was fine then, so this came as a surprise. Really appreciate the input, might have my mechanic check the wiring connections first before replacing any expensive parts.

Hey again! Thanks for those extra details about your X3. You know what's interesting, my X5 actually had really similar symptoms before the complete failure. The AUTO and AC buttons would work intermittently at first, and then just stopped responding altogether, just like yours. The fan would still run manually though. When I first got the "ECC" error, I was also worried it might be something major, but in my case, the intermittent operation was definitely due to that loose connection I mentioned. The vibration from driving would sometimes make it work, then not work, super annoying! Since you mentioned your fan speed controls are becoming inconsistent too, it's really sounding similar to what I experienced. My controls would act up especially when going over bumps or making sharp turns. The fact that it started right after your service is interesting, maybe something got knocked loose during the work? Before you spend big money on parts, definitely have them check all the connections first. In these BMWs, the wiring can get brittle over time, and connections can work themselves loose, especially around the climate control module. My mechanic showed me how the insulation had worn away slightly where the wires were rubbing against each other. Really hope it turns out to be something simple like mine was. Keep us posted on what you find out!

Thanks so much for the detailed follow-up! You've actually made me feel a lot better about this situation. Now that you mention it, I've noticed the controls do seem to act up more when I'm driving on rough roads or taking corners. That's a really good observation about the recent service possibly causing something to get loose, I hadn't even considered that angle. I just called my mechanic and mentioned your experience with the loose connection and worn wiring. He agrees it's worth checking that first before we start replacing expensive components. He's going to take a look tomorrow morning, and I'm honestly feeling quite hopeful it might be something similar to what you dealt with. Really appreciate you taking the time to share your experience in such detail. The similarities between our issues are pretty striking, and it's given me a much clearer direction to start with. I'll definitely update this thread once I find out what's actually causing the problem. Thanks again for your help!