The mod Railway Motor Car (0.6.0) caused a non-recoverable error.
Please report this error to the mod author.
I think I was standing a bit too far away at the time and tried to enter anyways. Probably was in some sort of twilight zone that was too far, but it still tried to enter anyways.

Error while running event railway-motor-car::railway-motor-car-key (ID 246)
Index out of bounds.
stack traceback:
[C]: in function 'newindex'
__railway-motor-car/scripts/use_equipment.lua:142: in function 'mount'
railway-motor-car/scripts/use_equipment.lua:212: in function <railway-motor-car/scripts/use_equipment.lua:197>