BMW i8 Hybrid Going Haywire, Multiple System Failures

Hey there! I have some experience working on hybrids and had a similar issue with my 2017 BMW i3. I feel your pain with those system glitches, they can be super frustrating! Had almost identical symptoms, unusual errors, nav failures, and control unit issues. Turned out the cable connection to the main control unit was faulty, causing intermittent communication problems with the BUS system. My local workshop found and fixed the loose connection, cost me about 155 Euro but solved all those annoying glitches. Before I share more specifics though, can you tell me if you're getting any particular error codes? Also, when did these issues start, and does it happen more often when the car is cold or after it's been running for a while? This info would help confirm if we're dealing with the same problem. By the way, my i3 hasn't had a single system glitch since the repair, so there's definitely hope for a proper fix here!

Thanks for sharing your i3 experience! My i8 just hit 178,080 KM and had its service last month. The issues started about 3 weeks ago, mostly when the car's been running for about 20-30 minutes. Haven't noticed any correlation with cold starts. Getting error codes P0A7F and U0164 pretty consistently. Tried disconnecting the battery for a reset, but the problems keep coming back. Really hoping it's just a connection issue like yours and not something more serious with the hybrid system. These glitches are driving me nuts, especially since everything was fine before! Let me know if you need any other details to compare our situations.

Hey again! Yeah, those error codes on your i8 are actually quite different from what I dealt with on my i3, so we might be looking at a different issue here. When I see P0A7F and U0164 together, especially after 178k on the clock, it's ringing some bells. In my experience working with these cars, those codes often point to the hybrid battery system communication. Had something similar happen after my battery service, turned out there was corrosion on one of the voltage sensing connectors that wasn't properly cleaned during maintenance. Caused all sorts of weird system behaviors, just like what you're describing. Since you mentioned it started after service, I'd definitely get them to check those connections again. The battery reset you tried was a good first step, but if there's an actual connection issue, it won't solve the underlying problem. When my i3 had similar symptoms (though with different error codes), it needed a proper clean and reseal of those connections. Mind if I ask if you've noticed any changes in your electric range or battery performance along with these glitches? That could help confirm if we're on the right track here.

Thanks so much for that detailed response about the battery connections. Come to think of it, I have noticed my electric range dropping a bit lately, used to get around 35km pure electric, now I'm lucky to get 28km. That definitely lines up with what you're suggesting about the voltage sensing connectors. I'll take it back to the service center and specifically ask them to check those connections and look for corrosion. Honestly, I'm relieved it might be something relatively straightforward rather than a major hybrid system failure. Really appreciate you taking the time to share your expertise and help diagnose this. You've given me a solid direction to pursue with the repair shop. Will update once they've had a look, hoping for a simple fix like yours! Thanks again for helping me narrow this down.