Why fan motor is not self started?
It depends on the motor. The fan is driven by an electric motor, and it can use a dc motor (as in a car) or an ac motor (as in a house). They are not interchangeable.
Synchronous motor or induction motor
Induction motor
As per the operating principle of the Synchronous motor, due to continuous & rapid rotation of stator poles,the rotor is subjected to a torque which is rapidly reversing i.e. in quick succession,the rotor is subjected to torque which tends to move it first in one direction & then in the opposite direction.Owing to its large inertia,the rotor cannot instataneously respond to such quickly-reversing torque,with the result that it remains stationary or in other words it is not self starting.
It depends on the speed of the motor that is driving the fan. There could be millions of answers to this question. I believe the questioner has asked the question wrong.
Could be a faulty fan motor, a faulty fan motor relay, a faulty fan motor temp switch or a blown fan motor fuse.
The 2005 Pontiac fan motor resistor is located on the back of the fan motor. The fan motor resistor is attached to the fan motor with two retaining screws.
Which fan motor?
No power to fan, fan motor is burned out, fan motor has seized up, control circuit for fan not working.
Remove the wiring harness or the fan motor belt, depending on the year of your Chevy Cavalier. Remove the fan motor retaining bolts. The fan motor will come off.
Bad fan motor? Dead short in wiring to fan motor?
Remove the wiring harness from the back of your 1994 Chevy heater fan motor. Remove the heater fan motor retaining bolts. Remove the fan from the front of the heater motor. Reverse the process to install the new heater fan motor.
The motor used in a table fan is usually a shaded pole motor.
A capacitor start motor is used in a ceiling fan.
The radiator fan sensor switch or the radiator fan motor are at fault (maybe even both). Wire the fan motor direct to see if it will run, if it does, replace the sensor switch. If the fan motor doesn't run, replace the fan motor before you buy a new sensor. If after replacing the fan motor, the fan still doesn't run, then replace the sensor.
Remove the wiring harness from the back of your heater fan motor. Remove the heater fan motor retaining bolts. Remove the fan from the front of the heater motor. Reverse the process to install your new heater motor.
There isn't a "fan motor switch", but there is a fan motor relay, located in the electrical box under the hood by the engine.