BMW X4 Alarm System Dead, No Beep When Locking/Unlocking

Hey there! I had a similar issue with my 2018 BMW X3 last year. I've got some experience working on cars, but nothing too advanced. The symptoms were exactly like yours, no beep when locking/unlocking, and the alarm system was completely unresponsive. After struggling for a few days, I took it to my regular workshop. Turns out it was just a faulty wiring connection to the alarm siren unit. The mechanic found a damaged cable and some corroded connector pins. They had to replace some wiring and clean up the connections. Cost me about 95 Euro and it's been working perfectly since then. Before I can offer more specific advice, could you share: Have you noticed any water damage in your car recently? Does your key fob work normally otherwise? Did this start suddenly or gradually? I'm curious because your X4 might have a slightly different setup than my X3, but these problems are often related to the same basic issues.

Hey again, and thanks for your detailed reply! My X4 just hit 195626 KM, and I've been keeping up with all regular maintenance, including the latest service. I haven't noticed any water damage, and yeah, the key fob works fine for everything else, just no beeping. The issue definitely started suddenly, like one day it was working fine, and the next, complete silence. You actually got me thinking about the wiring connection you mentioned. Makes sense since my error codes point to a communication issue. I'll definitely have my mechanic check those connectors and wiring first before replacing any expensive parts. Hope it's as straightforward as your case was! Did your mechanic have to keep the car for long to fix this?

Hey there again! Thanks for the additional info about your X4. No, my mechanic didn't need to keep the car for long at all, it was actually just a same-day repair. The diagnostic and fix took about 2-3 hours total. Since we already knew it was likely a wiring issue, they went straight to checking the connections first. Just to add to my earlier experience, I remembered something that might be helpful. Before taking it to the shop, I did try disconnecting the battery for about 15 minutes to see if it would reset the system (you know how these modern cars can be with their electronics), but that didn't help. So at least you can skip trying that step! The sudden onset of the problem in your case really does sound similar to what I experienced. When wiring goes bad, it usually fails completely rather than gradually. And since your mileage is pretty high (mine was around 180000 KM when it happened), these kinds of issues are not uncommon. One thing though, make sure your mechanic checks the water drainage channels near the siren unit while they're at it. Even though you haven't noticed any water damage, sometimes water can sneak in there without being obvious. That's what caused my wiring to corrode in the first place. Let me know what they find, I'm curious if it turns out to be the same issue!

Thanks so much for all this info, it's super helpful! Really glad to hear it was a quick fix for you. This makes me feel a lot better about booking it in with my mechanic. I've already called them and got an appointment for next week. I mentioned the wiring and connector issues you had, and they agreed it's a good place to start looking. They also appreciated the tip about checking the water drainage channels, apparently they've seen similar issues before. Honestly, I was worried it might be some major electrical system problem that would cost a fortune to fix, so hearing about your experience is really reassuring. I'll definitely get back to you once they've had a look at it. Fingers crossed it's just those connectors and nothing more serious! Thanks again for taking the time to share your experience. It's really helped me narrow down what to look for and what to expect at the workshop.