Have Ford Questions? Ask a Mechanic for Answers ASAP
I assume you have already tried but I would like to have you run the self test and see if any dtcs come up. If you get no codes than I suspect you have a bad head unit. Since you have another try swapping the head unit out. Let me know if you have any questions. These can be really sneaky and hard to diagnose the intermittent condition. But the only things that will cause your condition is the head unit or actuator.
1. To enter the self-test press the OFF and DEFROST buttons simultaneously and release, then press the AUTO button within two seconds. 2. The display will show a flashing blower icon for 20 seconds, after which all vacuum fluorescent segments will be displayed if there are no on-demand DTCs present. 3. If DTCs are present the EATC module will display "00 00" and then on-demand DTCs. Record all DTCs displayed. 4. If any DTCs appear during the self-test, carry out the diagnostic procedure. 5. To exit the self-test and retain all DTCs, press any button except DEFROST. The EATC module will exit the self-test and retain all DTCs.6. To exit the self-test and clear all DTCs, press the DEFROST button. The EATC module will exit the self-test and all DTCs will be cleared.
My mistake, the manual head unit still has the control module built into it. You just will not be able to run the self test. I suspect you have a faulty control module since you have already verified the actuators are working correctly. Just go ahead and swap out the head unit. This should correct the issues your having. Let me know if you have any other questions.
You already changed out the head unit?
If you have swapped out both the actuator and the control unit this leaves an intermittent issue that in my opinion has to be a bad connection in the wiring. I have verified the system via the electrical diagrams and there is nothing else in there that will control the output. You are going to need to verify what is happening when the problem is present. You should be getting proper signal. I am going to open this question back up to the experts and see if anybody can provide more details. Thanks
Seems to be either some wiring is chafed and occasionally rubbing, or the door itself is sticking at times. Do you have access to a long boroscope to snake down each vent including floor and defrost vents to observer the doors opening and closing to see if they are sticking.
Welcome I'm Chris aka Moose
The prior 2 experts have opted out and will not be helping any longer on this post.
Would you like me to try and diagnose this HVAC issue?
-----------About me and Just Answer------------
I am in my upper 30's, have a wife and 2 sons. I farm, fish, hunt, build, and coach youth soccer. I work on anything with an engine, been to many schools and classes through my 12 years with the dealership to get trained and certified. I try the best I can to share what I know and or have access to with my customers. Please consider I base my questions and answers to you, solely on the information you give me since I am not there to see, smell, hear, touch, or test. I try my best to be here everyday starting at 3pm central. Rating an answer is required. Please let me know if your not pleased prior to rating or if you cannot rate me so I can try to help a different way. God Bless and have a great day.