BMW X4 Climate Control Dead: AC & Heat Both Acting Up

Hey there! I had a similar issue with my 2019 BMW X3. The symptoms you're describing sound exactly like what I experienced last month. In my case, it turned out to be a faulty connection in the climate control module, not the solar sensor. When I took it to the garage, they found corroded pins in the main control unit connector. The temperature blend door actuator was also stuck due to the poor connection. It wasn't a major repair, but it needed proper diagnostic equipment to pinpoint the exact issue. The mechanic showed me how the connector pins had built up corrosion over time, which caused intermittent failures in both heating and cooling. They cleaned the connections and replaced the damaged pins in the harness. Since the fix, my climate control has been working perfectly. Given your symptoms, I'd suggest having the control module connections checked first before replacing any sensors. It's not a serious issue, but it does need someone who knows BMW electronics well.

Thanks for sharing your experience! That's super helpful. It does sound really similar to what I'm dealing with. Quick question, do you remember roughly how much you ended up paying for the repair? Also, has everything stayed working properly since then, or have you noticed any other quirks with the climate system? Cheers

Hey there! Just wanted to follow up, I actually took my X3 back to the mechanic after we last spoke, and it turns out I was wrong about the connector being the only issue. They found and fixed a solar sensor fault that was causing some of those problems too. The cable connection to the sensor was damaged, which was making the whole climate control system act weird. Total cost for fixing the solar sensor was 95 €, not too bad considering how much trouble it was causing. Honestly, it's been working like a charm since then. No more temperature control issues or error codes. The heating and AC are both spot-on now. My earlier repair with the connectors plus this solar sensor fix seem to have sorted everything out completely. Pretty relieved it wasn't anything more serious! Let me know if you need any other details about what they did. Always happy to help out a fellow BMW owner. Catch you later! Mark

Thanks again! Really appreciate all the info. Just wanted to update you, I took your advice and had it checked out yesterday. You were right about getting someone who knows BMW systems. Found a good mechanic who specializes in European cars. Turns out I had both issues you mentioned, the corroded connector pins and a faulty sensor connection. The whole thing cost me a bit more than yours, but honestly, it was worth every penny. The climate control is working perfectly now, both the AC and heating are back to normal. Such a relief to have it fixed properly! The mechanic was great too, showed me exactly what was wrong and explained everything they did. Really different from my last experience! They even gave me some tips about preventive maintenance to avoid similar issues in the future. Thanks again for sharing your experience, it really helped me make the right decision about getting it fixed. Have a good one! Cheers