I have an 02 1500 ram single cab. My AC/heater fan will only work on high. Can anyone offer any suggestions?

 

switch is out had it happen on a ford focus once

 

The blower fan motor works off of a resistor block that has several terminals coming off of it. Each one gives a certain voltage. At lower voltage the fan spins slower. At wide open speed you are using the terminal (via the switch on the dash) to get full 12-14v to the blower and run full speed. So it sounds like maybe you need to replace your blower resistor block.

 

Weed is correct, it's the resistor block (which is surprisingly expensive I might add). I had mice shred some insulation on top of mine and short it out. Fan did the same thing yours is. It's an easy fix. The block is right under the glove compartment on the passenger side. Two screws and it will drop right out.

Greg

 

This exact thing happened to me. There is a harness plug under the glove box that someone kicked loose. Just plugged it back in and my three lower speeds started working immediately!

 

Hi. Would this be the same location on 99 Dodge Dakota. One minute it will work normally but then in the next minute it drops to where the only place it blows is on high setting but in low blow speed. Thanks for your help.