Well, next time it happens, remove the steering column plastics, and behind the ign switch there's another little cylinder. You have to remove a small Philips head screw and it comes out. There's kind of like a "T" hole in it. From there stick something in and turn it counter-clockwise and see if that turns it off. If not, then follow the cables that lead off it down to under the dash, and unplug those cables. If it still doesn't turn off, then shit is really fucked up and I don't know what to tell you.