My old solenoid was frozen solid in the out position so the tractor wouldn't turn off. I took it out and ordered a new one. I put it in today and once plugged in it will only stay in the closed position. It has power to it all the time. What might cause this? Woud you think a short or bad key switch(can't find anything about this four pin switch), I am new to working on a tractor so help would be great. Thanks.