BMW Z4 Trunk Mystery: Tailgate Sensor Driving Me Crazy

Hi there! Last month, I had a similar issue with my 2018 BMW M4. The trunk was acting up, wouldn't latch properly and kept showing error messages. Initially thought it was just the latch mechanism, but turned out the wiring harness had some damaged cables near the hinge area, causing intermittent connection issues with the hall sensor. Had to take it to a specialist who found that the wires were getting pinched every time the trunk opened and closed. The insulation had worn through, causing shorts in the system. Not a critical safety issue, but definitely annoying and needed proper fixing. Required replacing the entire wire harness assembly and recalibrating the sensor. Your symptoms sound very familiar. I'd recommend having someone check the wiring connections first before replacing the sensor itself. A good diagnostic scan should point to whether it's a wiring issue or the actual sensor that's failed. Best of luck sorting it out.

Hey, thanks for sharing your experience! Yeah, that wiring harness issue sounds exactly like what I'm dealing with. Just curious, do you remember roughly how much the repair set you back? And has everything been working smoothly since they fixed it? I'm trying to figure out if I should brace myself for a hefty bill and if it's worth getting it done at a specialist rather than my regular mechanic.

Hey again! Good news, had my hall sensor issue completely sorted out! Only cost me 95 € to fix, which was way less than I expected. Turned out it was just a dodgy cable connection that needed fixing, nothing too major. Been working perfectly since the repair, honestly. No more error messages, and the trunk opens and closes like a dream now. The specialist I went to really knew their stuff, they spotted the issue straight away. Looking back, going to someone who really knows BMWs was definitely the right call. Regular mechanics might have just replaced the whole sensor unit, which would've cost loads more and might not have even fixed the actual problem. Trust me, for electrical issues like this, it's worth finding someone who specializes in BMW systems. They'll usually spot these smaller issues that can save you big money in the long run. Let me know how you get on with yours!

Thanks for the update! Really relieved to hear it wasn't too expensive and turned out to be a simple fix. You're absolutely right about going to a specialist, I've learned my lesson the hard way. I actually took your advice and found a BMW specialist nearby. Brought my car in yesterday, and guess what? Also turned out to be a loose connection! The mechanic showed me how the wire was getting pinched near the hinge, just like you mentioned. Total bill came to around 120 bucks, definitely better than the 500+ my regular mechanic was quoting for a full sensor replacement. Car's running perfectly now. No more error messages, and the trunk's working smoothly again. Really appreciate you sharing your experience, saved me both time and money! Sometimes it really pays to ask around before jumping into expensive repairs. Think I'll stick with this specialist from now on. Thanks again for all your help!