Ok I already replaced the thermostat and coolant and bleed it, that didn't work. I then replaced my upper radiator hose thermoswitch and I thought that fixed it. Nope, the radiator fan still comes on only when I turn off the engine. I asked the head tech at the local honda dealership and he said that the thermoswitch in the upper radiator hose is what controls the fan unit coming on after the engine is off. So I'm sure I replaced the correct one. And I know I'm NOT overheating because the temp gauge is right in the middle at three bars (4th gen) and the lower radiator hose is cool to the touch (its 30 degrees here so the rad. doesn't have to work very hard). Also I replaced the rad. cap with a new 16 lb one. Any ideas why the fan still comes on and only when the car is turned off?

 

Mine does this too, so long as they turn off after a while and your motor isn't overheating I wouldnt throw money at it.

 

It is just normal.

 

mine does this too, it turns off after a few minutes though. As long as it turns off like mine does i wouldn't worry about it. It's not really a big deal, maybe just a little irritating.

 

wow... the fan turns on to cool the car down instead of just letting the heat build up.

 

funny mine used to do this. then i changed one thing

that was the radiator + fans (off a jdm clip for my jdm h22)

and that fixed the problem. but i don't know, seems like i'm the only person with that fix

 

arent some of them electronic fans? i think my 93 is just a normal fan. I could be wrong but I seriously thought the 94-96 had electronic fans.

 

I didn't know that Preludes have this issue or at least mine doesn't. On my pops VW, the fan stays on for like 3 minutes after the car shuts off, but that doesn't happen on my lude. I guess it's a nice thing to have during really hot summer days/nights, but would def.. get annoying IMO.

 

on a front wheel drive car, the fans are always electric y0

 

usdm cars have a switch a and a switch b, switch a can only activate the fan when the ignition is ON, switch B can activate the fan EVEN when the ignition is off... switch A is the one on the thermostat housing. switch B, is the switch that is located on that small upper rad hose housing at the front of your block, next to the header. if you don't want your fan coming on after you shut your car off, you could technically just unplug that switch (don't worry switch A on the thermostat housing will still activate the fans when necessary when your car is running - it just won't be able to activate them when the car's ignition is off). JDM engines don't even have that switch B. I installed it on my car (with a jdm swap) cuz i figure why not let things cool properly.

if you want to test it - play with a paperclip and the ignition positions - but why bother.

p.s. i may have screwed up the switches names a/b - but the locations and functions are accurate (;


oops and after writing all that - i finally read the initial post. um i'd also check the fan relay...

....actually.. could be in the connector )to the thermoswitch) itself, unplug that greenish connector from your switch and make sure the two pins dont' have continuity to one another. one time after cleaning my engine bay i had that happen.. fan just fired up.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by oranginal &raquo;</TD></TR><TR><TD CLASS="quote">wow... the fan turns on to cool the car down instead of just letting the heat build up. </TD></TR></TABLE>

its 20 degrees outside temp and my engine fans should NOT turn on when I go for a 5 minuite drive and can touch the exhaust manifold and head for as long as I want and not get burned.

Do preludes have a fan timer switch like accords do? What would the symptoms be if that went bad?

 

are the fans staying on long enough to drain your battery? if not then why worry about it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by preludeguy_92 &raquo;</TD></TR><TR><TD CLASS="quote">are the fans staying on long enough to drain your battery? if not then why worry about it?
</TD></TR></TABLE>

it has before and the car was driven only 8 miles Thats kinda what I'm trying to say here, its not supposed to turn on and when it does I'm not sure how long it'll run. Its been anywhere from 2 minuites up to however long it takes to drain the battery. And I'm not gonna sit out in a freezing parking lot to wait for them to shut off, either. What about this fan timer switch?