BMW i3: Multiple Power Windows Failure & Error Code Issue

Hey there! I've got some experience working with hybrid cars. Had a similar issue with my 2014 BMW i8 last year. When all power windows stopped working at once, it turned out to be a dying vehicle battery. The computer system started acting up, showing unusual error codes and messing with the window controls. Took it to my regular workshop, and they diagnosed it pretty quickly. The original battery had reached the end of its life, causing electrical gremlins throughout the system. Got it replaced for about 290 Euro, and that fixed everything, windows, error codes, the whole deal. Before I jump to conclusions though, could you share: Does your key fob still work normally? Are you having any other electrical issues? Have you noticed the car being harder to start recently? Just want to make sure we're dealing with the same problem. BMWs can be tricky with electrical stuff, but usually there's a straightforward fix once you pinpoint the issue.

Thanks for the detailed response! Just had my service done 2 weeks ago at 112393 KM, and oddly enough, the key fob has been working perfectly fine. No starting issues either. The only problem is literally just the windows, all four stopped working simultaneously this morning. The dashboard shows the window button symbols lit up, but nothing happens when pressing any of them. Weird thing is, everything else electrical seems to be working just fine. The battery does seem like a logical place to start checking though, especially since these i3s can be quite sensitive with their electrical systems. Did your mechanic have to do any system resets after the battery replacement?

Hey again! Hmm, interesting that it's just the windows acting up. You know what, my case was actually a bit different from yours now that you've shared more details. When my i8 had the battery issue, it was causing multiple electrical problems, not just the windows. I remembered something else that happened with my i8 about two years ago, had a similar issue where just the windows stopped working. Turned out to be a faulty Body Control Module (BCM). The symptoms were exactly like yours, all windows stopped at once, dashboard symbols still lit up, but completely unresponsive. My mechanic did have to reprogram the BCM after replacing it. The whole thing cost around 450 Euro, but it's been working perfectly since then. Given that everything else is working fine in your case, and you've just had a service, I'm leaning more towards it being a BCM issue rather than a battery problem. Have you tried disconnecting the battery for about 15 minutes and reconnecting it? That sometimes resets the system and might get things working again. Worth a shot before heading to the workshop. If that doesn't work, I'd definitely get the BCM checked out.

Thanks for the clarification! That's super helpful, especially about the BCM potentially being the culprit. I actually haven't tried the battery disconnect reset trick yet, that's a great suggestion. I'll give that a shot first before taking it to the shop. Just tried calling my regular mechanic and he mentioned the same thing about the BCM being a common issue in these cars. At least now I have a better idea of what I'm dealing with and the potential costs. 450 isn't cheap, but it's better than what I was imagining! Really appreciate you taking the time to share your experience and troubleshooting steps. I'll try the reset tonight and update everyone if it works. If not, looks like I'll be scheduling a BCM check next week. Fingers crossed it's just something simple that the reset can fix! Thanks again for all the help. It's great having people who've dealt with similar issues share their knowledge.