BMW i3 Battery Warning Signals: Terminal 30 Mystery

Hey there! I had a similar issue with my 2018 BMW i8 Hybrid last season. Started with intermittent starting problems and battery warnings. The Terminal 30 diagnosis was spot-on in my case. Turned out the high-voltage battery management system was failing, causing excessive drain on the 12V battery. Took it to the garage and they found that moisture had damaged some connections in the battery management module. They had to replace the module and recalibrate the entire system. It was a serious issue that could have led to complete system failure if left unchecked. The fix wasn't just a simple battery replacement, they also had to update the battery control software and check all the connection points. My car's been running perfectly since then, no more warning lights or starting issues. Best to get it checked asap, these hybrid systems are complex and problems can cascade if not addressed promptly. Hope this helps.

Thanks so much for sharing your experience! This is super helpful and sounds exactly like what I'm dealing with. Really reassuring to hear you got it sorted out. By the way, do you remember roughly how much the repair set you back? Also, just curious, have you had any other electrical gremlins pop up since they fixed it? Cheers!

Hey there! Happy to give you an update! After I had that repair done on my i8, it cost me 290 € to fix the battery issue. Turned out it was heavily discharged and needed replacement. The mechanic also sorted out that Terminal 30 continuous plus problem I mentioned before, such a relief to have that fixed! And you asked about other electrical issues, nope, not a single one since the repair! My car's been running like a dream. The starting is crisp every time, no more warning lights, and all those error codes are history. Really glad I didn't wait any longer to get it sorted. The technicians did a thorough job checking all the connections and making sure everything was properly calibrated. Worth every penny if you ask me. These hybrids can be tricky, but once you get the electrical system sorted, they're fantastic cars. Let me know how you get on with yours!

Thanks for all the detailed info! I actually just got back from the mechanic today. Took your advice and didn't wait around, good call on that! They found pretty much the same issue you described. My battery management system was acting up and draining the 12V battery like crazy. The total bill came to about 320 €, a bit more than yours but still worth it to get everything working properly again. The mechanic was really thorough, replaced some corroded connections, and did a full system recalibration. Car's running perfectly now, starts right up, no more warning lights, and all those error codes have disappeared. Such a relief! Really glad I got it sorted before anything major went wrong. Thanks again for sharing your experience, it really helped me make the decision to get it checked out right away! Cheers!