BMW M2 Key Fob Failure: Quick Solutions & Real Costs

Hey there! I had a similar issue with my 2019 BMW M240i last month. Initially thought it was just the key fob battery too, but turned out to be more complex. The key showed "Battery in key empty" warning, and the car wouldn't recognize the key for keyless entry. Took it to the garage where they diagnosed both a dead key fob battery and a faulty key antenna in the car. The antenna wasn't properly communicating with the key anymore. It wasn't a super serious issue, but definitely needed proper diagnosis and repair. My key needed a CR2032 battery replacement, plus they had to reprogram the key to sync with the new antenna. The whole process took about two hours. Just make sure you go to someone who knows BMW electronics well, these systems can be tricky. Good luck with the fix.

Hey, thanks for sharing your experience! This really helps as my symptoms sound identical to what you described. It's good to know it wasn't just a simple battery swap in your case, I'll definitely keep the antenna issue in mind when I take it in. By the way, just curious, do you remember roughly how much you ended up paying for everything? Also, has everything been working smoothly since the repair? Just want to make sure I'm prepared for what might come up. Thanks!

Hey again! Happy to give you an update! Actually, I just got back from the mechanic last week. The good news is that in my case, it was just the key battery after all, much simpler than my previous issue with the antenna. They changed the battery and reprogrammed the key, and now everything's working perfectly. The keyless entry is back to normal, and those annoying warning messages have disappeared completely. The total cost was 37€, not too bad considering I was worried it might be something more serious! Way cheaper than when I had that antenna problem last month that I mentioned before. Everything's been working like a charm since then. The doors unlock smoothly when I approach the car, and there's no more "Battery in key empty" warnings on the dash. Such a relief! Just make sure whoever looks at yours knows their way around BMW electronics, even for something as simple as a key battery, the reprogramming needs to be done right. Let me know how it goes with yours!

Thanks for the follow-up! Actually, I took your advice and got it checked out yesterday. Turns out my situation was a bit different from yours. The mechanic found that besides the dead battery, there was a problem with the key fob's circuit board. Small crack or something, probably from that time I dropped it last month. Ended up needing a new key fob plus programming. Definitely more expensive than I hoped, set me back about 280 bucks! But at least everything's working perfectly now. No more standing in the rain trying to manually unlock my car! Funny thing is, this new mechanic I found was super transparent about everything. Showed me exactly what was wrong with the old fob. Such a refreshing change from my last experience! Think I've finally found a reliable mechanic I can trust. Thanks again for helping me out with this. Really appreciate you sharing your experience, helped me know what to expect!