Electronic Heater/AC Controls (EATC) air direction

[koda2000]

2000 Mountaineer w/EATC controls:

Does anyone know where in the heater plenum the door is located that controls where the air comes out from? I assume it's controlled by an actuator and I think mine may not be working. The reason I believe this is that no matter which location I select, the air flow seems to come out of all the vents equally (dash, floor and defroster). The only setting that seems to blow exclusively from the dash vents is MAX A/C. As far as I can tell the rear seat vents, work normally, but then they're either ON or OFF. I get good heat and A/C, but defrosting takes a long time as you can't get 100% of the air to come out of the defroster vents.

 

[1998Exp]

Disclamer: this is from my 1998 FSM, 2000 MY may be different.
There are actually two doors: floor/panel and panel/defrost. No personal experience with them, but according to the picture in the FSM they are both at the left (driver) end of the plenum. Both are vacuum operated. There is a lengthy troubleshooting procedure in the FSM, which is separate for the manual and EATC versions that I can't quote here - perhaps someone with the electronic version of the FSM will.
If both doors are inoperative I would suspect the vacuum source or the controller (in case of EATC) rather than the doors.

2000 Mountaineer w/EATC controls:

Does anyone know where in the heater plenum the door is located that controls where the air comes out from? I assume it's controlled by an actuator and I think mine may not be working. The reason I believe this is that no matter which location I select, the air flow seems to come out of all the vents equally (dash, floor and defroster). The only setting that seems to blow exclusively from the dash vents is MAX A/C. As far as I can tell the rear seat vents, work normally, but then they're either ON or OFF. I get good heat and A/C, but defrosting takes a long time as you can't get 100% of the air to come out of the defroster vents.

 

[koda2000]

Disclamer: this is from my 1998 FSM, 2000 MY may be different.
There are actually two doors: floor/panel and panel/defrost. No personal experience with them, but according to the picture in the FSM they are both at the left (driver) end of the plenum. Both are vacuum operated. There is a lengthy troubleshooting procedure in the FSM, which is separate for the manual and EATC versions that I can't quote here - perhaps someone with the electronic version of the FSM will.
If both doors are inoperative I would suspect the vacuum source or the controller (in case of EATC) rather than the doors.

Thanks, I've run the EATC self-test procedure with nothing conclusive displayed. If it's the EATC unit, I've read that the problems can be leaking O-rings on the solenoids. I can have it repaired (or buy a used one) for around $100, which isn't worth it to me. I suppose I can swap EATC's with another of my trucks to get a definitive answer, but it's a little bit of a PITA and I hate taking apart a working system to test one that isn't working. Maybe when the weather is nicer... If I can determine which door(s) are involved, I could try testing the door/actuator with a hand-held vacuum pump and the vacuum lines with a gauge, but as it's apparently 2 separate doors, odds are leaning toward the ETAC unit that's at fault.

Does anyone have a vacuum line diagram (or a link) which shows the EATC lines?

 

[97exploder19]

In auto mode my eatc blows on the floor only. I only can get it to come out the vents when I turn it off auto.

 

[koda2000]

In auto mode my eatc blows on the floor only. I only can get it to come out the vents when I turn it off auto.

actually, I never use the AUTO setting.