Dash Fan Setting 1+2 not working

[Tom Doniphon]

5/4/26; I have a 2010 XLT (108k) and the dash fan has a switch that goes from 1 to 4. The lower speeds at 1 and 2 no longer work. The higher speeds of 3 and 4 work fine and the switch knob turns without any problem, just no fan at the 1-2 setting. Anybody have a suggestion to fix?

 

[99WhiteC5Coupe]

5/4/26; I have a 2010 XLT (108k) and the dash fan has a switch that goes from 1 to 4. The lower speeds at 1 and 2 no longer work. The higher speeds of 3 and 4 work fine and the switch knob turns without any problem, just no fan at the 1-2 setting. Anybody have a suggestion to fix?

I’d suspect the HVAC speed control (resistor unit) that fastens to the lower HVAC case, under the glovebox area.

Check the wiring connector for a tight and clean connection, with no signs of charing. If the wiring and connector is good, you could replace the fan speed control unit (which fastens to the HVAC plastic case with several screws).

Some people call this part a blower resistor, but I think Ford’s part name for it is a speed control.

 

[Gary Waugh]

As stated, there is a resistor (it’s one unit but has 3 resistors inside) that controls the speed of the fan. The unit is prone to burning out over time, I suspect you need to replace the resistive unit.

 

[JerryT]

There’s a rheostat located under your glove box which controls the fan speed. I replaced mine in my 98 Expy and fixed the problem. It was reasonably easy to do. It was easier to just cut and splice the wires and replace the resistor.

 

[BlackBetty]

I’d get the part from Ford. It will cost more, but you won’t have to worry about quality, and fitment.

Have purchased several electrical items from AutoZone only to have the harness connector not properly line up with the vehicle connector.

Replaced with MotorCraft parts, and they snapped right in. This was experienced on both an ‘04 Expedition & ‘16 Expedition.

Found something that might apply to your situation… TSB SSM-48070