heater problems

2001 378 4 speed fan switch won't shut off, can't control heat setting, can't change where air discharges, can't switch between fresh air or recirculate either. First thing to stop was the discharge location then everything quit. Already changed resistor on top of air box that didn't fix it anyone had this before. Another odd thing if you turn key off then on and don't touch anything you can turn fan on and off but when you flip recirculate switch or turn location switch fan won't shut off.