A/C will not turn down

[cjcullen]

I started my 2010 Expedition Limited today and the air will not turn down. It is blowing full speed. It will not turn off either. The temp control works, but not the speed. Any ideas on what this could be?

 

[stamp11127]

Welcome to the site.

I don't have the diagrams for the 2010 but on the 2007 what you are describing can come a short to ground in the wiring harness for the EATC or a bad EATC module. You can pick up the OEM service manuals on dvd off ebay and the factory t/s methods can help you zero in on the problem.