This is a new one,,,,we never see this,,,F30 left rear door lock was not working once in awhile,,,,sometime it wouldn’t unlock or lock,,,,,sometimes it would be ok for several days,,,someone else put the left rear door lock actuator in hoping that would fix the problem,,,,I probably would have done the same thing ,,,,because we always have problems with the door lock actuator.  Well that wasn’t the fix,,,I noticed when I had the door open in certain positions,,,,and I tried to unlock or lock the door,,,,it would work or not work depending on the position the door was in when open,,,,I would then move the door and it would then start to work again,,,,,it was like there was a dead spot in the wiring harness inside the door,,,so we decided to replace the door harness.,,,,this is not a normal thing guys,,,,,don’t get any ideas ok,,,,lol