Ford Expedition 2017 PWM Speed control or resistor control?

[Huasteco]

Blower does not work on my Ford Expedition 2017. I have ruled out: Fuse, relay, motor, and blower speed control module. (Shorting Yelow/Blue to ground on the connector to the Speed Control Module starts the blower at max speed as expected, if this is an PWM (Pulse-Width-Modulated) control.



The only thing left is the HVAC Module DATC that produces the control signal for the speed control module. The questions I have are:

Although I am 99% sure this is a PWM and not a resistor control, a confirmation from someone else would be nice.

What kind of control signal is going into the Speed Control Module? (The smaller gauge wire White/Violet) Is it a PWM signal itself, or is a analog variable voltage (perhaps 0 to 12V) that determines the width of the PWM?

Where is the “HVAC Module DATC” and how to get to it? Any link to a video showing how to remove the dashboard would be handy.

Thanks!!!

J.

 

[woodmanjc]

I have the same problem with my 2017. I have 2 blower motors and have tested one and know it runs when supplied 12 volts, also have new resistor and connector installed. Any help is appreciated.

 

[sthomp99]

I am having the same trouble, 2016. The control module CCM25 controls the blower speed via PWM. The signal I believe is a square wave, 0 - 5 v, slow being wide 5v spikes, medium halftime 0v or 5v...

I haven't sourced replacement module, $200+, salvage yard next. Works HIGH all time bypassing any control, grounded blower motor ground wire. Found wire diagrams on this site. Attaching