A few things come to mind. Unplugged/broken vacuum line; Bad control panel switches; Bad vacuum actuator someplace; Plugged up with outside stuff like leaves.
The blower motor will operate when the key is in run regardless of whether the motor is running. The AC itself is not operating as the compressor is turned by the motor.
Probably the blower motor, wiring to it or control switch
If the heater blower has humming noise when motor is running, first check its capacitor. If the capacitor is fine, then the motor is the problem and may need to be replaced.
on a 1990 cadallic sedan de ville after you cut the car off the blower keeps running killing the battery
A blower motor that only works on high is normally caused by a defective Blower Motor Resistor Pack. DRL, do not have a clue.
turbo blower is an equipment where a turbine is attached with the blower part. steam enters through the turbine inlet and expands through the blades and goes to the outlet which helps the turbine shafts to rotate. this turbine shaft is attached with the shaft of blower that makes the blower rotating.
Defective Blower Motor Resistor Pack. Replace it.
most likely a defective blower module under the hood
The blower motor circulates the air through the system.
What can happen when a blower motor resistor goes bad is that the motor will run and then suddenly stop running on a regular basis. Sometimes the blower fan will not turn on and cause the motor to overheat.
When that happens on a Chrysler Town and Country with auto temperature, the blower motor power module has failed. It is also called a blower motor resistor.
Check the vacuum hose under the hood. May have a leak or have been disconnected. Also check - The blower - this includes its motor, fan and associated components/wiring. Next to check is the coil (this looks like a small radiator) through which the blower moves air is clogged. Check if the vents themselves are clogged.