Had a sciatic flare during the winter and couldn't do much. Better now and had a camping trip planned for last weekend. When I tried to lower the camper (after being up all winter), the top had settled a few inches and am not able to pull the safety cable to let it go down. When pressing the up or down button, it sounds like it is in a bind. Have not been able to find an owner's manual or any schematics for the wiring or lift system. Need HELP.