Remanufactured Engine Swap cooling fan issue:
 

Hello all this is my first post on the board. I just recently had a remanufactured engine put into my 2010 F-150 FX4. I am having an issue with the radiator fans kicking on to the highest setting right after startup. I live in Michigan and the truck sat all night in sub 40 degree temperatures and upon start up it goes straight to the highest setting.

Only thing I can think of is an air bubble in the cooling system. I have tried purging the system several times. Anyone have any ideas?

Thank you

Well first of all welcome to the forum and as for your fans is that they default to high speed operation if some part of the low speed electronics is malfunctioning (fuse,relay,etc.)

Thanks!

I appreciate the quick response. I will start there checking all the fuses and relays. Gives me a place to start. I have been scratching my head for a while.

Problem solved! I found a wire that was unplugged after a long search. All is well now.