I have a modern Lionel Berkshire 6-11389 that I have been running with no problems for over a year. In the last month the coupler on the tender has been randomly opening. I haven't changed anything on the layout or the consist running modern cars (3 log, 3 coal, 1 searchlight and 1 caboose). I can try to pull the coupler open manually and I cannot. This happens on regular track not switch tracks, etc. It occurs on straight and curved sections (I am using Ross track).
The coupler works normally when I open it via the cab remote.
Has anyone else seen something like this? Given that I can't pull the coupler open can I assume that it may the engine electronics randomly opening the couple or ?
Thanks for any suggestions.