Depends on the year. You could try the resistor first since it is the cheapest. If not that, then check the fuses, relays and wiring to the control head. Then lastly, change the motor.
Check to see if you are getting power to blower motor - if so replace blower motor If not check fuse, switch, resistor pack.
you need a new blower motor resistor with auto temp control
Defective blower motor resistor pack.
How do you replace a fan blower resistor on a vauxal Corsa?
Blown fuse, defective blower motor resistor pack, defective blower motor, or loose or disconnected wiring.
replace blower motor resistor. It is under the passenger side foot well.
replace the blower motor resistor. it is located on the firewall near the heater hoses.
If your talking about your blower motor only working on high its usually your blower motor resistor that has stopped working properly. (The blower motor resistor is an electrical component which limits the flow of electricity to your blower motor, allowing it to spin/blow at different speeds). It is easy to replace on some vehicles that have easy access to them because all you have to undo is usually two screws/bolts and one wiring connector.
Thermostat possibly stuck open or heater control valve broken. Now if you mean the blower motor has stopped working, check the fuse, blower motor itself, or the blower motor resistor pack.
It is most likely a bad blower motor resistor. Replace the resistor. If the problem continues, it could be the switch.
The blower motor speed resistor is burned out. You can replace only the resistor but the resistor probably burned out because the blower motor is going bad. If you want to fix it for good, replace both the blower motor and blower motor speed resistor.
how to replace blower resister on a 325i BMW 2002