2019 Exp Max - 3rd blend door actuator?

[darkphox]

Hi all,

Looking for insight on fixing the A/C in our '19 Exp to see if I can figure out what I've missed before I reach out to a repair shop...

In the front: cold air IS being generated and the blower motor ramps up and down with the fan speed dial. The problem is, about 3/4 of the time it refuses to let the cold air into the cabin. You can hear the blower motor blowing against what sounds like a closed vent somewhere beneath/behind the dash. I replaced two front blend door actuators, one on the driver side to the right of the gas pedal, and one on the passenger side. My understanding is these adjust whether the air comes from feet, dash, or defrost vents. I saw the 3rd gen Expeditions had a third actuator but couldn't find it. I'm thinking this one might control whether the air is allowed in from the A/C or heater systems. I tore the dash apart looking for it but couldn't find it. I'm assuming there must be a third actuator somewhere, I just don't know where. Appreciate any help finding it!

In the rear: cold air is NOT being generated. The actuator works (can switch between roof vents and foot vents) and the temperature DOES adjust. Hot gets hot, but cold only goes down to ambient temperature. I'm thinking it might have lost refrigerant, but I'm curious if there's something obvious I can try before taking that to get looked at. I've gotta tear the whole back right apart to get to it, again I appreciate any insight on what I might be missing before I go down that rabbit hole.

We live in San Antonio and the weather's already getting to the point where I'll have to start throwing money at it if I can't figure out what I've missed. Again, appreciate any ideas/insights!

 

[darkphox]

Quick update, I found the service manual on the sticky thread and learned a couple things from section 412-00. The actuators I previously replaced were the Air Distribution Door Actuator and Driver Side Temperature Door actuator. Looks like there's also an Air Inlet Door and Passenger Side Temp Door actuators that I'll look at next. Due to the intermittent nature of the problem, I'm not convinced it isn't a sensor somewhere, but I'll continue to RTFM.

 

[WedelP]

Did you ever get anywhere with this? My vehicle, 2019 Expedition Max, appears to have the same issue. Rear ac is ambient but will get hot. The front blows cold like 50 or so and will occasionally not blow air as you mentioned like it is being blocked by something even though you can hear air movement. I have had it connected to Forscan to monitor evaporator temps, actuator position compressor status and more but nothing seems out of the ordinary. Forscan also didn’t have any modules I could see the monitored the rear hvac control unit so I never got feedback on that.

Any feedback you have figured out is appreciated.