Do you just run a constant 12v to the cooling fan wire? The reason I'm asking is because I'm having overheating problems - due to my cooling fan not coming on + being boosted with a civic halfcore radiator.

Checked fuses and they're all fine.
Any help is much appreciated.

 

Boosted & you've got a radiator half as big as a stock Integra? Wonder why it's overheating...

If it overheats when you're driving (not stopped in traffic), then running the fan probably won't do you any good. Driving 50mph pushes more air thru the radiator than the fan would, anyway.

If the rest of your wiring is intact, you can jumper the wires for the fan switch, to make sure the fan runs. Then if you want you can wire a toggle switch parallal with the engine's fan switch so you can turn it on anytime you want.

 

It only overheats while I'm stopped at idle. Driving, it's fine.

 

Oops. I guess I really wasn't specific in this post.

Here's my other one that I accidentally posted in the Classifieds:

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">I took out my AC and replaced my Integra radiator for a Civic rad for my Turbo to fit. I always had the water temp needle at around 4/10ths - which always seemed fine. Recently, my Water Temps just skyrocketed all the way to hot after driving hard and then going to idle. Only the heater cools things down sometimes. I found out my fan was not working.
Has anybody encountered the same problem? I'm using my stock Integra fan base now. The fuse checks to be fine.
</TD></TR></TABLE>

 

If it was my car, first I'd figure out why the fan doesn't run. The fan switch is in the thermostat housing. Unplug it & jumper the wires together with a paper clip. Now your fan should run as soon as you turn on the ignition. On my car the engine doesn't have to be running for this to work.

If that works, then you've just demonstrated that the wiring, relay, fuse, & motor are OK. That leaves the fan switch itself. So get a new one.

If that doesn't work, you've already checked the fuse (right?) so check the relay. Mine hasn't screwed up yet so I don't know exactly where it is. If the relay is OK then you're gonna have to go checking wiring harnesses with a DMM. That can be a pain - good luck.

One more thing... What about the AC relay? I'd have to look up the wiring in my Helm book, but the AC relay might be involved somehow in this circuit. I think the AC can make BOTH fans run, so if you just pulled the AC relay you might have to put a jumper in there somewhere.