BMW iX3 Battery Issues: Terminal 30 Plus Investigation

Hey there! (Some experience with EVs) I had a similar issue with my 2021 BMW i4, and it sounds very familiar. My car started showing these exact symptoms, battery warnings and startup problems. Got it fixed at my regular workshop last month, actually. The problem turned out to be a faulty battery management system that wasn't correctly monitoring the charge levels, leading to the battery getting heavily discharged. Total repair cost me 290 Euro, but it was worth it as it fixed the issue completely. They had to recalibrate the entire system and check all the connections. Before jumping to conclusions though, could you share: How old is your battery? Are you seeing any other warning lights? Have you noticed any changes in charging behavior lately? If you're having similar problems to what I experienced with my i4, it might be the same issue. The iX3 uses a pretty similar electrical system to the i4, so the fix might be comparable.

Thanks for the input! My iX3 just hit 117831 km, and I had it serviced two weeks ago. Haven't seen any other warning lights, but noticed the charging's been a bit inconsistent lately, sometimes it charges super slow, other times normal. The battery's original, came with the car when I got it new this year. Took it to the workshop yesterday and they mentioned something about the battery management system, just like your case. Fingers crossed it's a similar fix. Really hoping I don't need any major repairs since it's still pretty new. Has your i4 been running smoothly since the repair?

Hey again! Great to hear back from you. Yeah, my i4 has been running like a dream since that repair, no more warnings or charging issues at all. It's interesting that you're having similar symptoms with such a new car though. My i4 was showing those problems after about 18 months of use, but yours is much newer. The inconsistent charging you mentioned is exactly what I experienced too. It was super frustrating, one day it would charge normally, the next day it'd take forever. Since the BMS (Battery Management System) repair, my charging speeds have been totally consistent again. Just to share what happened during my repair, they had to do a complete diagnostic reset and recalibration of the BMS. They also checked all the high-voltage connections since those can sometimes cause similar symptoms. The whole process took about 4 hours. Since your car's so new, this should definitely be covered under warranty. Mine wasn't anymore, hence the repair cost. Have they given you any timeline for the fix? Would love to know if it turns out to be the same issue as mine. Really hoping it's just the BMS and nothing more serious! The good news is, once they sorted it out, I haven't had a single problem since. Keep me posted on what they find!

Thanks so much for sharing those details about your i4 repair! That's really reassuring to hear it's been running perfectly since the fix. The workshop just called actually, they confirmed it is indeed the BMS causing the problems, just like in your case. They're doing the full diagnostic reset and recalibration tomorrow morning. Should take about 4-5 hours they said. You're right about the warranty, they confirmed it's fully covered since the car's only a few months old. The technician mentioned they've seen this issue a few times before in the new models, apparently there was a batch with slightly miscalibrated systems from the factory. Really appreciate you taking the time to share your experience, it helped me understand what I'm dealing with and what to expect from the repair process. Will definitely update you once I get it back from the workshop! Thanks again for all the help!