You can get a cable-luber for $9 or so. They are just a little clamp that has a rubber insert so you disconnect one end of the cable and slip the luber over it then attach a can on WD-40 by the red straw that comes with the can and just force the WD into the cable. When it squirts out the end you are done (as long as your cable doesn't have any cracks). This will make the cables last longer, help prevent freezing and help keep them from sticking. You can take a heat gun or hair dryer to your cable to thaw it out. I have had the same problem you have before I got the cable-luber (I love saying that!). I had to drive all the way back to the trailer using the on-off switch as the throttle.
1984 Yamaha YT 60 Tri Zinger(current project)
1983 Yamaha YTM 200 (rear suspension kit)..... long term project
2004 BMW R1150R
1972 Honda CT 70
2007 Lifan 110