BMW X4 Battery Warning Mystery: Real Issue or Bad Sensor?

Hey there! I had almost identical issues with my 2020 BMW X3 last season. Initially thought it was just the battery, but turned out to be the IBS (Intelligent Battery Sensor) giving false readings. The symptoms were exactly like yours, warning messages, dim lights, and difficult starts. After a bad experience with an independent shop that just kept replacing parts, I finally got it diagnosed correctly. The battery sensor was corroded and sending wrong signals to the car's computer. They had to replace the sensor and recalibrate the system. It wasn't a major repair, but it needed proper diagnostic equipment to fix it right. Quick tip: make sure they check the alternator too while they're at it. In my case, everything else was fine, just that faulty sensor causing all the drama. Hope this helps with your decision.

Thanks so much for sharing your experience! That's super helpful and sounds exactly like what I'm experiencing. I'm really glad you mentioned the IBS, makes total sense now with all these false readings I'm getting. Just curious, do you remember roughly how much you ended up paying for the sensor replacement and recalibration? Also, has everything been working smoothly since the repair, or have you noticed any other electrical quirks?

Great to hear back from you! Yeah, I remember our chat about those battery issues, glad I could help point you in the right direction. I actually just had mine fixed last week, and it cost me 315 € for the whole job (sensor replacement and recalibration). Since getting it sorted, my X3's been running like a dream, no more warning lights, no more cranking issues, and those annoying flickering lights are history. The battery sensor was definitely the culprit, just like I suspected. My mechanic showed me the old sensor, and it was pretty corroded! It's such a relief not having to worry about whether the car will start every morning. Seriously, it's been smooth sailing since the repair, no electrical gremlins or any other issues popping up. Best money I've spent on the car in a while, if you ask me. Let me know how yours works out!

Thanks for all your help! Just wanted to update you, I got my car fixed yesterday and you were spot on! Took it to a certified mechanic who diagnosed the corroded IBS right away. Ended up paying about the same as you did, and honestly, it was worth every penny. The whole process was pretty quick, they had it done in a couple of hours. The mechanic was super thorough and even showed me what was wrong with the old sensor. It's amazing how such a small part can cause so many problems! The best part? My car's running perfectly now, no more warning lights, strong starts every time, and those annoying flickering lights are gone. It's like having a new car again! Really appreciate you sharing your experience, saved me from going through multiple mechanics and unnecessary repairs. Thanks again for pointing me in the right direction!