BMW 6 Series Door Lock System Failure: Solutions Inside

Hi there! I had a similar issue with my 2004 BMW 5 series (and previously owned a 3 series too). I have some experience working on cars, mostly basic maintenance stuff. When my central locking failed, it turned out to be a faulty wiring connection near the door handle. My mechanic found corroded cables that weren't properly sending signals to the locking mechanism. The repair involved replacing some wiring and a connector, cost me around 95 Euro and fixed the problem completely. What's the exact error code you're getting? Also, does your key fob battery work fine? This info would help me understand if you're dealing with the same issue I had.

Thanks for sharing your experience! My car just had its latest service, sitting at 89719 KM. I've checked the key fob battery and it's perfectly fine, but I'm still getting error code 394. The doors out of nowhere lock and unlock on their own sometimes, which is super annoying. I've tried disconnecting the battery for a reset but no luck. Really hoping it's just a wiring issue like yours and not the whole control module, those things can cost a fortune to replace! Did your car show any other weird electrical issues before you got it fixed?

Thanks for the follow-up! Yeah, I totally understand your concern about those unusual door locks, mine did the exact same thing before I got it fixed. And funny enough, I also tried the battery disconnect trick first! Actually, before the wiring issue was discovered, my BMW did show some other quirky electrical behaviors. The windows would sometimes do this weird thing where they'd roll down slightly by themselves, and the trunk would occasionally pop open without pressing the button. The dome lights would also flicker now and then. All these issues disappeared after fixing the corroded wiring. Error code 394 sounds really familiar, that's exactly what my car was showing. The good news is that while it seems scary, it doesn't necessarily mean a full module replacement. In my case, the corrosion had spread a bit further than initially thought, so the repair ended up costing about 140 Euro in total because they had to replace more wiring than expected. Still way cheaper than a new control module! Have you noticed if it happens more often when it's damp or after rain? That was a telltale sign with mine, the problems would get worse in wet weather. If that's the case with yours too, it's probably the same wiring issue I had.

Really appreciate all that detailed info, it's super helpful! You're spot on about the weather thing actually. Now that you mention it, the unusual locking does seem to act up more when it's been raining. And yeah, come to think of it, I've noticed my dome lights flickering too, but I honestly thought I was just imagining things! This makes me feel so much better about the whole situation. I was already mentally preparing myself for a massive repair bill, but hearing that yours was fixed without needing a new module is such a relief. I'll definitely mention these symptoms and the weather connection to my mechanic, might save them some diagnostic time. Think I'll book it in next week to get checked out. Fingers crossed it's just corroded wiring like yours was. Thanks again for sharing your experience, really helped put my mind at ease about this whole thing!