BMW 7 Series Won't Start: Immobilizer System Issue

Hey there! I've got some experience with BMW hybrids. Had a similar issue with my 2014 BMW 5 Series Hybrid last year, and it drove me nuts! Your symptoms sound exactly like what I dealt with. The immobilizer light was flashing and the car just wouldn't cooperate. After trying a few things myself (I have some basic car knowledge), I took it to my trusted workshop. Turned out the key's programming was messed up and wasn't communicating properly with the car's immobilizer system. The fix was pretty straightforward, they reprogrammed the key, and it cost me 45 Euro. Car's been running perfectly since then. Before I can help more specifically, could you share: Have you tried using your spare key? Are there any other warning lights on the dash? Did you recently replace or repair anything related to the electrical system?

Thanks for jumping in! The immobilizer issue is still bugging me despite trying both keys. Mine's also at 35233 KM and had its last service just two months back. No other warning lights except the immobilizer one. The weird thing is, I did have some work done on the battery management system about a month ago. Could that be related? I'll definitely try getting the key reprogrammed first, that's way cheaper than what I was worried it might cost. Been breaking my head over this for days now!

Hey again! Actually, you mentioning the battery management system work really rings a bell. On my 5 Series, I initially thought it was just the key too, but after digging deeper, it turned out that any work done on the electrical system can sometimes mess with the immobilizer settings. In my case, after the key reprogramming didn't fully solve it, we found out that the battery management system wasn't properly "talking" to the immobilizer module. The technicians had to resync the entire system, basically getting all the electrical components to play nice with each other again. Honestly, given that you've had recent work done on the battery management system, I'd bet good money that's your culprit. My advice would be to head back to the shop that did the battery work and have them check the connections and programming. They should be able to sort it out pretty quickly since they're already familiar with the recent work. And don't worry too much about the cost, even with the full resync, it shouldn't be anything crazy. Mine came to about 150 Euro total, including diagnostics. Way better than replacing major components! Let me know how it goes, I'm really curious if your issue turns out similar to mine.

Thanks so much for the detailed insight! Just called my mechanic and explained everything about the battery management system connection you mentioned. They're going to check both the key programming and the system sync tomorrow morning. Really hoping it's just a communication issue between the components like in your case. The 150 euro estimate is such a relief, I was honestly preparing myself for something way worse! My mechanic seemed pretty confident once I mentioned the recent battery work too. They said they've seen similar cases where electrical work triggered immobilizer issues. I'll definitely update you once it's sorted. Really appreciate you sharing your experience, saved me a lot of worry and probably money too! Amazing how similar these issues can be across different BMW hybrid models.