when my car did this it was a blown fuse
Your blower motor working even after the car is off is a good sign. This means that the car's system is preventing your car from overheating.
Loose connection or blower motor is bad
Replace the blower motor resistor.
faulty blower motor resistor
down uner the glove box
There is a removeable panel below the glovebox. It is in front of the blower motor against the firewall. It has a wire connector from the loom and then it plugs into the blower motor
connection could be loose. Or the switch might be going out
The blower motor speed resister is burned out. This part is available from your local auto parts store.
I owned a 75 model Impala and the blower motor was located under the hood, passenger side of vehicle,down in the fender/fender well area, hiddenbehind a/c unit
where is the blower motor on a 2001 chevy blazer
If you are referring to the blower motor speed control, and you only have one speed, then the blower motor resistor pack is defective and must be replaced.
check the fueses check fueses