blower fan won't turn off

I have a 2003 Envoy with variable speed blower(6 speeds I think) stays on all the time on high speed even when I turn the car off and pull the key out. For the time I am just unplugging the blower when I get out. Any idea's? Thanks for the help.

Welcome to AF, when you are under the dash doing this, try disconnecting the blower relay/fan speed resistor first, if the blower shuts off it is bad,( the relay) common problem. It's on the blower case behind the glove box, slightly to the left.

Thanks for your help, repair was successful with a blower motor resistor. Easy fix, very easy install, about 10 minutes. donj303