I did a manual to automatic swap on a 2010 SSV about two years ago. Most everything works, but I have a blend door issue that required me to swap the driver and passenger blend door wiring. For it to work “properly” in manual mode, I need to use the passenger control to manually change the temperature.
Things that may not work:
Of course, the dual zones won’t work without replacing the plenum.
The outside temperature on the dash will always read 75, (but you have the temperature on the EATC, so it shouldn’t be an issue). I guess you could always add another outside air temperature sensor.
My SSV did not have a console. I purchased one, but never wired in the rear controls, so I get an error message if I run EATC Self Diagnostics.
That’s all the problems I have encountered, except for having to swap the driver and passenger blend door. You may not have that problem, but it drove me nuts. If you find a solution, please let me know. The next step for me to try to fix this problem is to load an asbuilt from another vehicle and see if that works.
This site was helpful during my conversion:
https://www.f150forum.com/f4/how-install-automatic-air-your-f150-212023/
I think you may have a problem with a later model EATC. I used an EATC from a vehicle with the same year and Connectors 228A and 228B fit perfectly. In my search to resolve my blend door issue, I tried a few different EATC modules. Many of the modules are for ’07 – ’11, but there are some that are only for ’07 and ’08. I don’t what the difference is, but the model that was only for ’07 and ’08 did not fit my 228A and 228B connectors.
If you connect Connector 228A and Connector 228B to the new EATC, all the blend doors will function and rear controls will function without any other modifications. I don’t remember if I tried to use the old blower switch with the EATC connected. I think I was afraid to because the EMTC is running the power to the switch (which is why it’s 10 or 12 AWG). The easiest way to address the blower motor resistor swap, is to find a donor vehicle and replace the blower motor harness. Make sure it is the same year, because the connectors are different. Just remember, once you remove the resistor and cut your plenum to make the relay fit, it’s not so easy to go back.
I installed the inside air temperature sensor and sunload sensor, but if you are only going to control the temperature manually, you probably won’t need it (but you will get errors when you run the EATC Self stics).
It’s been a while since I did this, but I may be able to help if you run into any issues.