BMW i3 Hybrid Stuck in Emergency Mode, Trans Tips?

Had a similar issue with my 2020 BMW i8 Hybrid last year. The symptoms you're describing sound exactly like what I went through! Initially thought it was the transmission fluid too, but turned out to be an undervoltage problem in the electrical system. My workshop ran a full diagnostic and found that the voltage was dropping below the required threshold, which triggered the transmission's emergency mode as a safety measure. Cost me around 240 Euro to fix, they had to recalibrate the voltage regulator and check all the hybrid system connections. Now it runs perfectly, no more warning lights or erratic shifting. What's your mileage, and have you noticed any other electrical issues like flickering lights or slow starter? Also, when exactly did these symptoms start showing up? This info would help me give you more specific advice based on my experience.

Thanks for sharing your experience! My i3 is at 65680 KM and just had its service last month. Haven't noticed any electrical issues or flickering lights, but the transmission problem started suddenly last week during my morning commute. Interesting that your issue was related to the voltage regulator, that's definitely something I'll have checked out. The symptoms are very similar to what you described. Did your car also make any unusual noises before the transmission went into emergency mode? I'm hoping it won't be too expensive to fix, considering the car is still relatively new.

Hey again! Yeah, actually now that you mention it, my i8 did make a slight whining noise right before going into emergency mode, kind of like a high-pitched hum that wasn't there before. It started around 58000 KM, pretty close to where you're at now. Since you just had service done last month, I'd definitely get back to your workshop and have them check the electrical system. The sudden onset without any other electrical symptoms is exactly what happened to me. The tricky thing with these hybrid systems is that they can mask electrical issues until they hit a critical point. What's interesting is that you're having this right after a service. Did they do any work related to the hybrid system during the service? In my case, they found that one of the connections had worked slightly loose after some routine maintenance, which contributed to the voltage issue. I'd recommend getting it checked soon though, driving in emergency mode for too long isn't great for the transmission. Mine took about a day to fix once they identified the problem, and the workshop gave me a full report showing the voltage readings before and after. Keep me posted on what they find!

Thanks so much for the detailed follow-up! That whining noise you mentioned, I've actually started noticing something similar in the last couple of days, though I initially thought I was just being paranoid. You're absolutely right about getting it checked quickly. I've already called the workshop and booked it in for tomorrow morning. During the last service, they did some work on the hybrid battery cooling system, so your comment about loose connections after maintenance really rings a bell. I'll make sure to mention this to the mechanic, along with the voltage regulator issue you experienced. It's such a relief to hear that your fix was relatively straightforward and didn't take too long. Really appreciate you taking the time to share all this info, it's given me a much better idea of what to expect and what to discuss with the workshop. I'll definitely update you once I know what's going on with mine. Fingers crossed it's just a similar voltage issue and nothing more serious!