OK, here’s the problem. I have four different A/C & heater blower speed settings: off, 1, 2, and 3 (3 being the highest setting). The blower doesn’t work on setting number 1 or on setting number 2, but will work on setting number 3, which is very annoying due to the large amount of air it pours out. If anyone can explain to me why this is happening and how to fix it I would greatly appreciate it.
You probably have a bad blower motor resistor. These are generally not difficult to change and are usually located behind the glove box in the heater ducts.
If the vehicle has fairly high mileage on it, you might consider taking at look at the blower motor also. When a blower motor ages it takes more electrical current to turn it. The current has to flow through the resistor to operate the fan motor and more current means more heat, which in turn can burn the resistor out.
Most people don’t own them, but an inductive ammeter can be used to determine blower motor current draw. A higher than normal amp reading means the motor is dragging and needs replacement.
Hope that 'splains it and helps you out.
Blower motor resistor. $36.99 @ Advance Auto Parts store. Haynes repair manual.
Thank you for your quick replies. I will look into buying a new resistor.
I had a 89 Nissan Stanza, With the same problem you describe. I replaced blower resistor and it worked for a while. The second time I pulled the blower motor and cleaned it. Check where the armature is and blow it out with compressed air. I was able to soldier one side of the open blower resistor back together and it worked fine. Leaves stuck in the blower motor will also cause high current. It must spin easily.