Happy Christmas y'all!
After a two failures (2017, 2018) which were repaired by a SeC (200Euro, parts warranty) it got stuck a couple of weeks ago again. While I had searched extensively at the first and second failure, this time I've searched only a bit, coming up with the same frustrating results. So I scheduled an SeC appointment.
After 2-3 weeks I was able to open by coming from behind and after twisting the left and right hand rubber stoppers into the tailgate and giving it a push after closing while at least one door is open, I managed to use it again. Then it got stuck again on the 22nd. This time I searched more intense and found newer videos and this thread and this helped a lot!
I pulled the fuse one time to see if it would help, wasn't enough. Then managed to open it after the car went into sleep by "sneaking up from behind"... since I disabled "passive entry" there was not much sneaking necessary. I left the car unlocked for >30minutes, until the door handles pulled themselves in and it went into energy saving, helps activating the option "always go into energy saving" and disable "always connected". While pushing the tailgate switch and immediately pushing with some force I could feel some resistance but was able to open anyway.
Then with the newly learned knowledge from the videos and what I've read here I pulled the "black plug" three times while hearing some sound from the actuator. The fourth time was nearly nothing to hear. Btw, my mid 2015 produced S85 has the black plug at the bottom and power lift gate
fuse no 42.
While having at least one other door open the tailgate is now able to open and close automatically and the actuator keeps being silent. I guess the fully inward twisted rubber stoppers allows the tailgate to slam shut when a door is open and the cabin pressure is not in the way.
Since I live in Germany, I was able to order the actuator directly at the MB online shop for 65Euro including taxes and shipping, expected delivery 2-4 days. Looking forward to change the part by myself and add a follow up.
All in all, thanks a million to y'all for sharing! Oaito.
PS: I was wondering, instead of pulling the "black plug" several times, did anyone tried to accomplish the same with pulling/reinserting the fuse a couple of times? I am not curious enough to get the tailgate stuck on purpose only for trying. But if someone has the issue, perhaps before trying the black plug you could identify the fuse for your model and pull, count to five, insert, repeat four times and try if this unlocks the actuator?