Questions/Comments: I have a Ford Edge Limited AWD 2012 Whenever I start my car or my car is running, my HVAC fan, either on auto or not, will increase or decrease in speed ON ITS OWN.... Then you have to hit the opposite speed of what it does Then it does it again. Then again you have to decrease the speed... Then again it increase the speed... sometimes this goes on for 5 to 10 minutes, sometimes it stops. You can have the AC off and it will turn on by itself again. It might start again for a couple more times or maybe not. I've unpluged the battery, changed the battery, resat the sync, Any Suggestions??????

 

Some later vehicles have modules that carry out the request of the operator and the switches. It sounds like the HVAC module has a mind of its own and may be causing this. A capable scan tool may be required to confirm this.