how hard is it to fix?the car was already warm.
htd catalyst,sec air system,ac refrig mon are on my tester are they related? on 2003 Ford Expedition
Could be. Sounds like this one built for California emissions. Maybe problem with your air pump.
how do i find out and begin to fix it?
Well did the codes all come up at one time or were the problems stacking? I'd start with problem with secondary air injection system. Check all hoses around air pump. Air pump may also have simply blown fuse. If this one not working will effect the catalyst efficientcy.