Z3 Active Hood Fault: Airbag Warning Needs Expert Fix

Hey there! Had the same issue on my 2003 BMW Z4 last year. The active hood sensors are part of the pedestrian protection system, and when they fail, they trigger both the hood actuators and the airbag light. Last time at the garage, they found that moisture had gotten into one of the acceleration sensors, causing it to send false signals. They had to replace both front sensors and reset the system. The actuators also needed replacement since they deploy like airbags, once triggered, they can't be reused. It's actually a serious safety system, so I wouldn't drive too long with it malfunctioning. These sensors are designed to detect impacts and lift the hood to create a crumple zone, protecting pedestrians in case of an accident. In my case, they needed to order specific parts from BMW and it took about two days to complete the repair. The system worked perfectly after that, and no warning lights since then. I'd suggest finding a garage that specializes in BMW safety systems, as this isn't a repair for general mechanics.

Thanks for sharing your experience! Glad to hear you got it sorted out. This is really helpful as I'm dealing with the exact same symptoms. Everything you described matches what I'm seeing with my Z3. Quick question, do you remember roughly how much you paid for the whole repair? Also, has everything stayed working properly since then, or have you noticed any other quirks with the system?

Hey again! Great to hear back from you! Just wanted to let you know that my Z4's active hood system has been working perfectly since getting it fixed. The repair turned out to be exactly what I suspected, a faulty acceleration sensor. Total bill came to 315 € and honestly, it was worth every penny. Haven't had a single warning light or any other issues since then. I was actually pretty relieved it wasn't anything more serious. These sensors can be tricky, but once they're replaced properly, they usually stay problem-free. My mechanic mentioned it's a pretty common issue on these models, especially as they age. Been driving the car for about a year since the repair now, and everything's still working like a charm, no warning lights, no false triggers, nothing. The system's doing exactly what it should. Just make sure whoever works on it knows their way around BMW safety systems, it really makes a difference. Hope this helps with your decision! Let me know if you need any other info.

Thanks so much for that detailed follow-up! You know what, I actually just got mine fixed last week. Wanted to share how it went since you were so helpful. Found a good BMW specialist and took it in. Turned out pretty similar to your case, faulty sensors were the culprit. Had to wait a few days for the parts, but the repair itself wasn't as painful as I expected. The mechanic was really thorough and explained everything. The work cost me a bit less than yours, around 280 €, and they threw in a full system check too. Been driving for a few days now and everything's working perfectly, no warning lights, no alerts, nothing. Such a relief to have it sorted! Funny thing is, I was so worried about picking the wrong mechanic again, but this time it worked out great. They really knew their stuff with these BMWs. Thanks again for pointing me in the right direction with all the specific details about the sensors and actuators. Really helped me know what to expect and what questions to ask. Just glad to have my Z3 back in proper working order!

I have a mercedes glc 300e on the display it says warning for active pedestrian protection see instruction manual. The car has a warranty. but the insurance company does not approve the damage. there is no damage report, time etc they say. Can you fix this yourself or workshop.

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Start by checking if there are any visible obstructions or dirt around the sensors and cameras related to the pedestrian protection system, as these can sometimes trigger warnings. If the issue persists, it's best to have a professional inspect it, especially since it's a safety-related system. Given that your car is under warranty, I recommend contacting your Mercedes dealership for assistance. They should be able to diagnose and fix the issue under warranty terms. Let me know how it goes or if you have more questions!