BMW M4 Tailgate Malfunction, Hall Sensor Issue?

Hey there! I had a similar issue with my 2014 BMW M3 last year (some experience with BMWs). The tailgate was acting up just like yours, super frustrating! Turned out it was indeed a faulty connection in the wiring harness. Took it to my regular workshop, and they found that one of the cables going to the tailgate sensors had worn out and was causing intermittent connection issues. The fix wasn't too complicated, they replaced the damaged wiring and connectors. Cost me around 95 Euro and it's been working perfectly since then. If you're experiencing the same symptoms I did, it's likely a similar electrical issue. Before I can help more specifically, could you tell me if you're getting any warning messages on the dashboard? Also, does the tailgate make any unusual sounds when you try to operate it?

Thanks for your input! My M4 has only done 5841 KM since my last service and I'm quite surprised to face this issue so early. The tailgate doesn't make any weird sounds, but it just stops mid-way when opening or closing. No warning lights on the dash, just the error code that shows up when I scan it. Your wiring harness suggestion makes sense though, might be worth checking that first before replacing the entire sensor unit. Did you notice if the problem got worse in certain weather conditions?

Hey again! Yeah, I totally get your frustration about facing this issue with such low mileage. Actually, when I had my wiring problem, I noticed it was way more noticeable during wet weather, the tailgate would act up more frequently then. Now that you mention your tailgate stops mid-way without any weird noises, it's sounding even more similar to what I experienced. Just to share more details from my experience, before I got it fixed, I tried cleaning the contacts and checking for obvious damage myself, but couldn't spot anything visually. The workshop later showed me that the issue was pretty subtle, the wire insulation had worn through in a spot that wasn't easily visible without taking things apart. One thing I didn't mention in my first reply, after they fixed the wiring, they also recalibrated the tailgate system. That was actually included in the repair cost I mentioned earlier. If you're planning to get it checked, make sure they do the calibration too. It made a real difference in how smoothly everything worked afterward. Have you noticed if it happens more often when you first start the car, or does it act up out of nowhere throughout the day? This might help narrow down if it's definitely the same issue I had.

Thanks a lot for the detailed follow-up! Yes, now that you mention it, I have noticed it acting up more when it's damp outside. That's really interesting about the wire insulation, makes me think we might be dealing with the same problem here. I haven't paid attention to whether it happens more at startup, but I'll definitely keep an eye on that now. I'll take it to my regular mechanic this week and have them check the wiring first, especially around those hidden spots you mentioned. Really appreciate the tip about the calibration too, I'll make sure they include that in the service. You've saved me from potentially replacing an expensive sensor unnecessarily! The funny thing is, I've been babying this car since I got it, so it's actually a relief to hear this might just be a relatively simple wiring issue rather than something more serious. Will update once I get it checked out, might help someone else with the same problem in the future. Thanks again for sharing your experience, it's been super helpful!