BMW i4 Electrical Gremlins: Dash & Light System Failures

Hey there! I have some experience working with EVs, and I had a similar issue with my 2018 BMW iX3 (also worked on my cousin's i4 before). Had almost the exact same symptoms, wonky speedometer readings and purple xenon lights. Turned out to be a faulty cable connection to the main control unit. The workshop found that some connectors were loose and slightly corroded, affecting multiple systems. Got it fixed for around 95 Euro, they basically had to clean the connections and replace a couple of damaged cables. Pretty straightforward repair once they identified the issue. Before I suggest anything specific though, could you share: How long have you noticed these issues? Have you spotted any other electrical quirks? Did you get any specific error codes? This info would help me understand if you're dealing with the same problem I had.

Thanks for the detailed response! I've had my i4 for about 3 years now, last serviced about 2 weeks ago at 25186 KM. The issues started showing up just a few days ago. Didn't get any specific error codes, just the general warning light on the dash. No other electrical problems that I've noticed, but the purple xenon lights are definitely concerning me the most. The speedometer issue comes and goes out of nowhere. Your experience sounds pretty similar to what I'm facing, I'll have it checked for those cable connections you mentioned. Hopefully it's just as straightforward to fix!

Hey again! Thanks for the extra details about your i4. Yeah, that definitely sounds identical to what I experienced. After fixing mine, I actually learned something interesting, these symptoms often show up around the 25-30k km mark because that's when those connector points start getting affected by normal wear and tear. Just wanted to add that after my repair, I noticed the cable connections needed a bit more maintenance than usual. I now get them checked during every service just to be safe. It's saved me from having the same issue pop up again. Quick tip from my experience, while you're waiting to get it checked, try not to use the xenon lights more than necessary. When mine started going purple, using them extensively made the problem worse pretty quickly. Also, keep an eye on your battery levels, these electrical gremlins can sometimes drain it faster than normal. Let me know how the repair goes! I'm curious if it's the same connector issue I had. Should be a pretty quick fix if it is.

Thanks so much for all the advice! That's really helpful to know about the maintenance schedule for those connectors, I'll definitely make sure to get them checked regularly from now on. Good tip about limiting the xenon light usage too, I've been trying to avoid driving at night anyway until I get this sorted out. I've actually just booked the car in for tomorrow morning at my local BMW workshop. Mentioned the connector issue you described, and they seemed to think that could be the likely cause. Fingers crossed it's as simple and affordable as your repair was! I'll be sure to update you once they've diagnosed it properly. Really appreciate you taking the time to share your experience, it's made me feel a lot more confident about getting this sorted out.