My AC and my heat in my car only works on high, what is the problem and how do i fix the problem?

Answer 1

It is most likely the fan control switch, bypass the switch (some disassembly required) and see if the fan works on the other settings.
If so, replace the switch. Problem resolved.
If not, then this indicates a problem with the fan itself. Replace it and any capacitor on this circuit.
Just be happy the thing works, glass half full kind of thingy...
Autozone may help you to diagnose the problem

Answer 2

The blower motor resistor is usually under the dash attached to the blower motor itself or near it. it is a small little thing with a plug and wires attached to it. Some are easy to remove some are not because of the lack of space under the dash.

Answer 3

Your blower motor resistor is out and will only operate on full voltage and
none of the other settings will work..

Answer 4

Go see a car technician