Blower motor assembly with blades. The HVAC Blower Motor is responsible for circulating climate controlled air within the cabin of the vehicle. A centrifugal fan attached to an electric motor via a drive shaft spins and moves air through the system. If you notice the climate control is not adequately blowing air through the vents this may be an indication of a blower motor issue. Common problems with the blower motor manifest themselves as bearing failure and loud noises, or completely quitting. If the blower works on some settings but not others, check your blower motor regulator as well.