Blower Motor won't shut off

I have a 2001 Suburban with 115,000 miles. Recently then climate control blower motor remained on when the Ignition was off and the keys were removed. The only way to shut it down was to remove the the front HVAC 30 amp fuse from under the hood.
 
Can anyone tell me why the blower would continue to run with the car off? How can I Fix it?

i would assume a short in the wires somewhere between the fuse and the motor

if it was a short it would blow fuse check blower motor relay

blower motor switch(shorted out)?