Good evening, are you saying that the blower motor stops working? If so then the most likely cause will be a melted wiring harness connector at the blower motor controller. The proper repair will be replacing the blower motor, the blower motor controller and the wiring connector at the blower motor controller. It isnt a cheap repair. It is a common concern that I have personally seen numerous times. You can wiggle the blower motor controller connector and get it to work momentarily. Here is some more info related to this concern:
The cause for this failure may be the motor, or blower wheel assembly. Debris from the environment may attach to the wheel causing additional weight, and drag on the motor. If the motor is worn from age, the effort to operate the motor could cause high current draw. Verify current draw with an amperage meter. Amp draw should be approx (13-17) amps when blower is operating on high mode
Alternative repair method
Some owners have elected to repair the wiring by soldering wire splices directly to the terminals inside the blower motor control box and not using a connector.
The blower motor cost about $180.00 and the blower motor controller cost about $130.00. Some of these prices change.