Dolphin Nautilus STILL not moving

Hi,

I have a Dolphin Nautilus pool cleaner that suddenly just stopped moving. The impeller motor works but no movement (I can move the treads by hand.) As I was taking it into my local dealer I noticed that the cable had been cut (Probably by my lawn guy) and upon looking I realized I had the easy one to replace.  Ordered the cable, replaced it and put the cleaner back in the pool.  Still no movement.  Now I am baffled.  Any ideas?  It is clean - I made sure of that.

Thanks,

Theresa Sandifer