06 Expl Heater Fan stuck full blast/can't stop!

[Kirkwwhite]

Out of the blue my 2006 Explorer heater fan started blowing at full speed. Heats and A/C at proper temps just fine, but the fan controls will NOT work, even though they say fan is at level 1 or 5 it is constantly at top nosiest level of air blowing. Does the same with Auto function or if I choose to defrost, or floor heat, or whatever.
How do I get it back under control? I can't talk in the car anymore it is so loud from the moment the key is turned on.
thanks.

[shorod]

It sounds like you have the electronic automatic climate control. If that's the case, it sounds like the blower motor controller is fried. Seems unusual for a 2006 though. Do you still have warranty on the vehicle?

I had the blower motor controller fail on my 1993 SHO many years ago in the same manner IIRC. It's a Pulse Width Modulated motor controller with a transistor for the adjustable speeds and a relay for high speed. When the solid state portion failed, I think the motor went full speed until I replaced the controller. I'm pretty sure it defaulted to high speed rather than no speed like the mechanical blower motor resistors would.

-Rod

[Kirkwwhite]

The car is no longer under warranty. Has 45k on it. It has lots of bells and whistles so pretty sure it has electronic auto temp controls as I rarely touch the heater except to adjust temp up or down. All electronic and no manual knobs. It normally auto increases or decreases fan as needed on its own.
Can I replace the controller on my own? Where would it be located and hope best to get to it?
Thanks.

[shorod]

Yep, if it's all electronic controls, its the electronic automatic temp control. The blower motor controller will be located in the air box where air from the blower motor can blow across it. You will likely need to access it from either under the dash or behind the glove box. Some models had the blower motor resistor under the hood, but I don't think the blower motor controller ever ended up under the hood.

-Rod