My fan speed dial only works on high,could it be a resistor,if so where is it located?

If you have a fan that has different speed settings (1234, or low med high etc) and the only one that works is high - then the blower resistor pack has failed. If you have a climate control unit (where you just pick a temp you want) then the fan is controlled by the heating system and it sets fan speed. If you have climate control style try lowering the temp to a lower setting (current temp in vehicle) and see if fan slows down. If not then climate control unit or fan resistor bad. If dial type and you get nothing on lower settings (only high works like mentioned above) you need to change blower resistor. It is located under dash near the fan itself. Look for small unit bolted in duct near fan with wire plug going to it.

the fan speeds work through a blower motor resistor and not separate fuses for each speed. when these resistors go bad they are designed to work on high speed only.

I would replace the blower motor resistor first then see if that corrects this. The resistor is located next to the blower motor under the dash.

When the blower fan will only work on high speed setting this means the fans speed control resistor is burned out, when it fails the fan defaults to high speed only. The fan resistor is located next to the fan and held into the cooling air duct by 2 screws near the blower motor. The part is fairly cheap and easy to replace.

Hello sanjuis24
It sounds like you've got a bad blower motor resistor. The resistor is located under the right side of
the dash at the blower motor. A new resistor is not very expensive and it's a fairly easy DIY.
Hope this is helpful

Usually when the blower fan only operates on hi speed, its because of a failed blower motor resistor. You still have hi speed because on hi, the power going to the blower motor goes directly to it, as opposed to the lower speeds, when the power is routed through the resistor, thus lowering the voltage, which in turn lowers the speed of the fan. The resistor is usually located near the blower motor itself, under the hood back near the firewall.

Check the blower resistor pack - usually located in the heater air ducting in the blower fan airflow. Check for loose connections and open circuit resistors on the unit.
If speed 4 works always, its unlikely to be the blower motor ground connection.

http://www.physics.sjsu.edu/becker/physics51/images/27_01_Resistors_in_series_and_parallel.JPG

Ok i know this might be a little difficult to understand. BUt If you click on the link above. Find Diagram (a), That picture represents your switch, not complete but in theory. each Resistor means a Different speed. As you turn the Dial it applys current to all the resistor depending on which one it points to. As you can see the (i) represents current and lets say R3 represents "speed 5" Well in theory the less resistors the fast the speed. So the at low speed the dial will be pointing to R1 at medium fan speed the dial will point at R2 and at high Speed "speed 5" the Dial points to R3. Less Resistance More Current More Current more Speed. Now You have No R3...
This basiclly means that the who switch wihich includes Warm and cold and 1,2,3,4,5 and Defrost etc need to be replaced for 5 to work again.

No solution Replace switch

If you are looking for the fan blower resistor, it is located behind the glove box. No tools need to get to it and a nut driver to remove the 2 screws to replace it. A 20$ part. It has 2 sets of wires coming off of it. A do it yourself fix.

There is a resistor attached to the blower box. Replace the blower resistor and this should solve your problem