It looks like you have some low voltage wires that I think might go to magnetic sensors that detect when the cover is fully open and fully closed. The sensors and switch should go to a control box. It could be a bad circuit board in the control box. The motor might also have an automatic shutoff based on motor current or other torque related measurement. The motor might have a clutch that limits the torque to protect the ropes from breaking if the cover binds. The clutch might need to be adjusted. If the motor continues to run with no cover movement, then the clutch is likely disengaging the motor (the same thing as in a cordless drill).
The nylon bearings, pulleys and gliders might be binding. If the tracking if off by even a little bit the gliders will bind. If the track is oxidized then the gliders will bind. Based on how oxidized the reels are, I'm guessing the tracks are also oxidized.
If it has never worked correctly, then it was likely not installed exactly right. I think that the cover is due for a full overhaul.
What manufacturer made the cover system?
What is the model?
When was the system installed?