BMW i4 Battery Warning Signs: When Your EV Won't Start

Hey there! I had a similar situation with my 2019 BMW i3s last year. From your description, it sounds like what I dealt with, a failing power distribution unit (PDU). In my case, it started with weak auxiliary systems and flickering lights, just like yours. Initially, I got misdiagnosed with a 12V battery issue, but the real problem was more complex. The PDU was malfunctioning due to a previous software update that wasn't properly installed. This created a chain reaction affecting multiple systems, including the power management and start-up sequence. The repair involved reprogramming the entire power management system and replacing the PDU. It was definitely a serious issue that required specialized knowledge. These electric BMWs are complex machines, and when one system fails, it can trigger multiple error codes. Since you're dealing with symptoms very similar to what I experienced, I'd suggest finding a certified BMW EV technician. The diagnostic equipment they use is specifically designed for electric BMWs and can pinpoint these kinds of interconnected issues. Hope this helps with your decision making.

Hey, thanks for sharing your experience! That PDU issue sounds exactly like what I'm dealing with. Quick question, do you remember roughly how much the repair set you back? Also, has everything been running smoothly since the fix, or have you noticed any other quirks? Would love to know what to expect if I end up needing the same repair.

Hey again! Great news, I can actually give you a really positive update on this! After getting it properly diagnosed and fixed, my i3s has been running like a dream. The best part? The repair didn't cost me anything because BMW acknowledged it was a consequential error from that botched software update I mentioned. They covered it under their technical service campaign. Since the fix, I haven't had a single issue with starting the car or any of those annoying electrical gremlins. The flickering lights, weak systems, error codes, all completely gone. It's been about a year now, and honestly, it feels like I'm driving a different car. The power delivery is smooth again, and all the auxiliary systems work exactly as they should. If your symptoms are matching what I had, definitely get it checked out by a certified BMW EV specialist. They'll know exactly what to look for, and if it's the same PDU issue caused by a software problem, you might not have to pay anything either. Just make sure you're clear about the symptoms and mention the possibility of a PDU issue related to software updates. This could save everyone time in the diagnosis process.

Thanks so much for all the detailed info! I finally got the courage to take my car in yesterday to a certified BMW EV specialist. You were spot on, it was the PDU issue! The mechanic was really knowledgeable and even mentioned they'd seen several similar cases. The best part? Like in your case, they found it was linked to that software update problem. After showing them my service history and the error codes, they contacted BMW directly. Guess what? They're covering it under warranty! I'm so relieved I didn't have to shell out thousands for this repair. The car's at the shop now getting fixed. The mechanic says it should be ready tomorrow, and they're doing a full system check to make sure everything's properly updated this time. Can't thank you enough for sharing your experience, you saved me from another potential nightmare with my old mechanic. I'll update you once I get the car back, but I'm already feeling much better about the whole situation!