BMW i3 Multiple System Failures, ASC/ABS Issues Explained

Hi there! I had similar issues with my 2017 BMW i8 Hybrid last year. I've got some experience working on cars, but nothing too advanced. My car showed almost identical symptoms, ASC light, jerking during acceleration, and the ABS acting weird. After a couple of failed attempts to diagnose it myself, I took it to a workshop. Turned out the ASC relay was defective and needed replacement. The whole thing cost me around 90 Euro, and the car's been running smoothly since then. I've noticed these issues are somewhat common in BMWs, my who owns a 5-series had similar problems. Could you share some more details about your i3? Like when did these symptoms first appear, and have you noticed any specific conditions when they get worse (like wet weather or after the car sits for a while)? This info would help me give you more specific advice based on my experience.

Thanks for sharing your experience! My i3 just started showing these symptoms last week. You mentioned the ASC relay, that's really helpful to know. Just had my latest service about 2 months ago and everything was fine until now. It does seem to get worse when I first start driving, especially during the initial acceleration. The jerking is pretty consistent though, regardless of conditions. I've noticed it happens more when the battery level is below 50%. Did you experience anything similar with the battery level correlation? The ABS light flickering is really starting to worry me.

Hey again! Thanks for those extra details about your i3. Yeah, now that you mention the battery level correlation, I actually noticed something similar with my i8 before I got it fixed. When my battery dropped below 40-45%, the jerking was definitely more noticeable. I think it's because the ASC system struggles more when managing power distribution between electric and combustion modes at lower battery levels. The ABS light flickering, that's exactly what mine did too! It would flicker especially during the first 10-15 minutes of driving. The mechanic explained that the faulty ASC relay was causing interference with the ABS system because they're interconnected in these hybrid models. Quick question, have you checked if the regenerative braking feels different too? In my case, it felt really inconsistent before the relay replacement. Sometimes it would be super aggressive, other times barely noticeable. I'd really recommend getting it checked soon though. I tried driving with these symptoms for about two weeks before getting it fixed, and honestly, it just got worse. The repair itself was pretty straightforward once they identified the problem, took them about 2 hours total.

Thanks so much for all this detailed info, it's really helping me understand what's going on! Yes, now that you mention it, the regenerative braking has been super unpredictable lately. Sometimes it feels like it's barely there, and other times it kicks in way too hard. I was actually wondering if that was related or just my imagination, so it's good to know you experienced the same thing. I'll definitely get it checked out this week, don't want to risk making things worse by waiting too long. Your experience with the ASC relay issue sounds exactly like what I'm dealing with, especially with how the symptoms get worse with lower battery levels. Really appreciate you taking the time to share all this, especially the bit about the repair being straightforward. Makes me feel a lot better about getting it sorted. I'll probably ask the mechanic to specifically check the relay first, given how similar our issues are.