My Santa Fe F unit has developed an interesting problem. After running for a few minutes, the horn sounds spontaneously and will not disengage! It shuts off if I reverse the unit and then comes back on when it goes forward. If I shut the unit down and let it sit for awhile, the horn shuts off, then comes back on in a few minutes! WTF is going on. I am tempted to just disconnect the horn, unless that would screw something else up!