If you try manually telling a train to go to a path designated as the opposite direction as it's current track when the two tracks are joined by a bi-directional track it fails to navigate there unless you move it to the bi-directional track. In the screenshot the faulted train was told to go from it's current track to the track below that one.
What you're saying is a train can't navigate somewhere if the route involves changing directions, correct?
Not necessarily. The route is fine assuming it has to stop on a bi-directional track, this only occurs when giving a manual order to go between the two tracks.
What route?
I guess its only a bug in manual orders right?
yeah, this is in your save, I noticed it trying to rearrange the trains you had on the track
still working on troubleshooting. However, related to this issue, it seems in a different spot the pathfinding works, so I'm gonna need more diagnostics to find the specific scenario for that.
Okay, so I think I found the specific scenario for this issue. Its when the bi-directional track that is connecting just terminates, IE the train can't go through a loop to turn around. If there is a loop it seems to work fine. (see new screenshot)
So its when the train has to switch directions to continue on the path
specifically if it needs to switch directions by going onto a bi-directional path that dead ends. So a very specific scenario. And its easy enough to work around by telling the train to go to the bi-directional part, and then onto the part you wanted originally.