BMW Z4 Airbag Light & Convertible Top Mystery Symptoms

I had similar issues with my 2014 BMW M4 last year. After multiple warning lights, including the airbag warning, the diagnostic revealed an affected control unit that was causing problems with both the safety systems and convertible top sensors. Initially, mechanics were pointing at various sensors, but it turned out the main control module was defective and needed replacement. The issue was quite serious since it affected multiple safety features. In my case, they had to replace the entire control unit and reprogram the system. What made it particularly concerning was that the faulty unit could potentially prevent the airbags from deploying in case of an accident. The repair wasn't just about convenience, it was a safety-critical fix. Sounds like your symptoms match what I experienced. Make sure you get it checked by a certified BMW specialist who can properly diagnose the control unit. Don't drive too long with active airbag warnings.

Thanks for sharing your experience! Really helpful to know about the control unit being the culprit. My symptoms do sound pretty similar to what you described. Mind if I ask how much you ended up paying for the whole repair? Also, has everything been working properly since the fix, or have you noticed any other quirks popping up?

Hey there! Happy to give you an update. I took my M4 to a certified BMW specialist and they fixed everything, cost me 1000 € to replace and reprogram the faulty control unit. Since then, everything's been running perfectly smooth! The rollover sensor is working as it should, and I haven't had a single warning light come back on. To be honest, it was worth every penny for the peace of mind. The convertible top works flawlessly now, and more importantly, I know all the safety systems are functioning correctly. My advice would definitely be to get it sorted sooner rather than later, especially with those airbag warnings. No other issues have popped up since the repair, which was about 8 months ago now. I'd say once you get the control unit replaced, you should be good to go. Just make sure you're using a certified specialist who knows what they're doing with these systems. These BMWs can be tricky if you don't have the right diagnostic tools and expertise.

Thanks so much for all the details! Actually, I just got back from a certified BMW specialist yesterday. You were spot on, it was the control unit causing all the trouble. Paid about the same as you did, and they had to keep the car for a day to complete all the programming. The mechanic showed me the old unit and explained how it was affecting multiple systems. Got everything fixed up now, no more warning lights, and the convertible top is working perfectly again. Such a relief to have it sorted, especially knowing all the safety systems are back to normal. Really glad I asked here before trying another unusual mechanic. Would have probably wasted more time and money going down the wrong path. The peace of mind is definitely worth the cost. Time to enjoy driving my Z4 again without worrying about those warning lights!