so on this 2004 sedan i have when you turn heat on in defrost mode both rad and ac fan come on and when up to operating temp it doesnt blow very warm unless your really going on hwy coolant level is good and no overheating im puzzled any takers on this one im probably missing something obvious perhaps thanx

 

when you turn on the defrost feature the ac automatically comes on because cold air works better to defog a window. with that being said there is a process to defuse the ac feature when utilising the defrost function. How to disable the A/C while using the defrost mode - 7th Gen Honda Forum - The #1 Community for 2001-2005 Honda Civic Enthusiasts
it worked for me.

 

Note that disabling the A/C function of defrost mode will also disable the ability to defog the windshield. Don't seem advisable.

 

yeah thanks its actually the rad fan im concerned with as it seems to go on with ac fan even when cold

 

That's how it's designed. What's the problem?

 

Both fans are running though ac fan and engine fan im thinking it should just be ac fan

 

Again, the system is designed to run both the radiator and condenser fans when the A/C is turned on. Leave it alone.

 

okidokee thanks i guess im just used to old vw,s thinking somethings always wrong

 

In 2001 they changed the design to a full-width condenser in front of the radiator instead of the half-width independent side by side arrangement of 1992-2000. Thus on the later models, both fans flow air through the condenser, so they should both come on.