'94 pusher fan manual switch

H

HSKR

Registered User
With the hotter temps just around the corner(and right in your face for some of you), I decided to figure out a way to help keep our cars cooler. Since I own a '94, have a manual for it on cd-rom, and can't drive the car because I need head gaskets(which I can't afford right now) Anyways, here is a quick write up on how to easily install a manual switch to turn on the pusher fan(which never seems to come on by itself) whenever you want as long as ignition is on.

Should work on '95's as well, but my manual only covers '93-'94 and it doesn't work on '93s(or my manual on CD-rom is wrong) Anyways, the pusher fan relay is mounted on the drivers side fender behind the shock towers. It's the only relay mounted there so easy to find. All you need to do it mount a switch for switched 12VDC. Either splice in, or shove a wire into the bottom of the relay to make contact with the small orange wire, and route it to your switch. The other side of the switch needs to be on a 12VDC source. It can be a switched 12vdc from ignition since this will only work with ignition on. Once you have the switch hooked up, you can try it out. Turn on ignition, then turn on the switch. It should trigger the relay and turn on the front pusher fan. This will help keep engine cool, and also moves air across the intercooler.

Now, I have only experimented with this on my car since it's down right, but it did work. Nothing better for me to do than tinker with things, and since I work with electronics for a living, it's something I enjoy.
 
Cool thing man...i did this on mine a while ago! What I did to keep things on the safe side was override the relay, apply constant 12v to the fan, and connect ground to the switch. I had the switch sitting inside my console for a while, but i never liked it there. I have a 94 5speed which didnt come with the trac. assist button on the info center, so what I ended up doing was hooking the pusher fan to the trac assist button. Took me a while to get everything working right. I changed the bulb on the trac assist button and it lights green "OFF" when the fan is off. It looks factory and works just as I wanted it to!
One thing i will tell you is that the pusher fan is too small to cool off by its self. I tried it alone and it did nothing, so i thougth it was a waste of time. But!...try it in conjuction with your big fan working....it makes alot of difference then! If you think about it..while the big fan is pulling air through...the pusher fan crams more air in there...so it makes sense why for put it there. Not soo useless after all! But the temps that are pre-programed for it are just ridiculous. i want to see if later I can find a stock pusher fan to put in my 89...that would be sweet.
 
The puller fan is the "big" fan...theone inside the engine bay...the pusher fan is on the 'outside' of the radiator...much smaller and thin.
 
trife86 said:
i might sound like a idiot here but by pusher fan do you mean the fan behind the radiator?
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I think only the '94-'95 SC had the pusher fan in front of the radiator. And when used in conjunction with an intercooler fan, should keep your intake charge fairly cool.
 
CaifanSC said:
One thing i will tell you is that the pusher fan is too small to cool off by its self. I tried it alone and it did nothing, so i thougth it was a waste of time. But!...try it in conjuction with your big fan working....it makes alot of difference then! If you think about it..while the big fan is pulling air through...the pusher fan crams more air in there...so it makes sense why for put it there. Not soo useless after all! But the temps that are pre-programed for it are just ridiculous. i want to see if later I can find a stock pusher fan to put in my 89...that would be sweet.
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Not to sure the fan is too small, but just not mounted in the right spot. It's not centered on the actual radiator so when it's on, it's only blowing air across half the radiator. Not enough airflow to keep the radiator cool. I think if you wanted to center it on the radiator it might be enough by itself, but pusher fans have never been very efficient for cooling. That's why most people use pullers with a shroud to ensure airflow across the whole radiator.
 
That's a nice idea, because I find running the low speed fan all the time (IRCM low speed wire cut & spliced into the high speed) seems to keep the car TOO cool around town. But does anybody know what triggers that additional pusher fan in the first place. I heard it's a safety if the temp rises above 228 deg or the main fan fails. I also heard it's because the 134a refrigerant isn't as efficient as the old R12 and this fan helps the condensor during very hot weather ? I like the idea of adding a 12 volt source to trigger the relay, but where is it getting it's signal from in the first place?
 
i relocated my pusher fan today.your right,its way off to the side of the radiator,i centered it up,ran the wires for the switch.i didnt hook it up yet,im gonna get the same switch as the high speed fan switch i installed 2 years ago.it seems to move a good bit of air though?
 
Im interested in seeing how the fan works after being relocated. Please post the results guys. On another note ddw350, i see you are in Frederick, im located in Laurel..on the other side of I-95. Have u visited the local boards man (www.mamn12.com)?
 
i can only get my fan to turn on if i ground the orange wire i tapped into? it will turn on if i connect the orange wire to a hot source with the ign off...but when i have the car running,i have to ground it then it clicks and runs smooth..evidently,the thin orange wire is hot with the car running,then grounding it out trips the relay and turns the fan on?..no ihavent visited the local boards,but i will..thanks
 
im assuming you are tapping into the orange wire going into the relay...if im not mistaking that pin will act a certain way when the relay is receiving a 12v in put (ignition) and a different way when its not. Thats probably why you can have the fan work with 12v sometimes and sometimes with ground. If you are going to add a 12v input to have the fan run, do it to the dark blue wire which brings power to the fan its self..but use an inline fuse. I opted to do this at the fan (add power to the fan directly) and put the ground to the switch...just to complete the circuit. Definatelly check out the local boards man..we have a good following of tbirds...and more and more SC's are surfacing. There are plans to go to the track on the 8th...close to you...mason dixon dragway in hagerstown.
 
what amp fuse did you use? i did the same thing with my high speed fan,i tapped a wire[cant remember what color] ran hot to a switch from ign source.i think i used a 20 amp fuse for that.would there be any trouble with running my orange wire from the relay to a switch thats grounded? then it will only work when the car is running.whats the advantage either way?so you tapped a wire to the blue at the fan[or did you cut it] then ran that wire back to the switch,then grounded the other post on the switch? just curious...i havent been to mason dixon in years,friends of mine still go all the time..
 
If I remember correctly I used a 30 amp fuse...but one of the small tiny ones. I used a 20 amp before but it kept blowing on me, and the amp that is designated for teh pusher fan on the distribution box is also a 30 amp. What I did was tap into the harness connector that plugs to the fan, pulled out the blue wire (i have a thing about cutting wires) and plugged a different wire into the harness...so the harness just plugs like factory and I just have the blue wire tied to the harness and covered with electrical tape. The wire that replaced the blue wire is attached to the battery with a 30 Amp inline fuse. I then used a quick-connect thingy and tapped into the ground (BK) wire close to the fan and ran that wire to the inside of the car. If you attach that wire to a regular toggle switch you could probably just connect it to a good ground in the chassis, and the other side of the switch to the wire and it would work. I like making things harder on my self so I used the Info center off of an automatic 94+ mn12 and used the trac assist button to use as my switch...which is a completely different story. The reason why i didnt feed a hot wire to a switch is just for safety...in case the wire gets rubbed or cut and it touches ground i wont have a short circuit or sparks...it will just activate the fan b/c the circuit would be complete. About hagerstown, well yeah man ...bird people go there all the time! You should come with us man!
 
I'm a bit confused here. The blue & yellow wires are the power and ground that run directly to the fan (presumably via the fuse in the underhood box). The red is the 12v power source for the relay and the orange is some sort of signal wire to/from the EEC. The whole idea of using the relay (just like on the main fan) is not to have to run a new high amp power source through a suitably rated wire, switch and in-line fuse. I don't know what triggers the 12v red relay wire (coolant sensor maybe); but surely all you need do is cut the red wire (don't want to just splice it and backfeed 12v to the sensor), connect another wire with a switch in line back to a small power source. I installed an extra fuse box next to the dead pedal myself, so I only needed one decent 12v source tapped into the main box & then used, from 1amp-5amp circuits for my radar detector, pod lighting, I/C fan relay, etc. The only other question I have is regarding the orange sensor wire. If you don't disconnect it, what does the EEC do when it gets a signal saying that the coolant is 228 deg and the extra fan came on?
 
Joisey, You could do as you said...cut the red wire and provide the relay (through the cut red wire) with a switched 12v. source. I didn want to cut any factory wires, so I did it differently. In the relay the ground is provided through the mounting bracket/bolt that are screwed into the body so there is no ground wire, and that red wire is just the signal from the EEC telling the relay to close and make the fan work...the actual 12V power supplied to the fan comes from the yellow wire which comes from the distribution box in the engine. The orange wire...well i assumed (when i did the sketch) that it had to do with the eec...but in neither the shop manual or the EVTM sais what that wire is for or where it goes. But thinking about how relays work, it might just be another one of the terminals that are not necesarily used.

One question...what type of extra fuse box did you use? I think im also going to need another one to have fuses/relays for a couple other projects that I have in mind...but im into the whole factory look...so i dont want just anything. I was thinking of getting a full distribution box out of a crown vic...it has room for fuses, some of the hughe fuses, and relays...but i dont think i can find space to mount it inside the engine bay..maybe the trunk..but i would have to run wires to it all through the car.
 
Okay, after reading the latest replies, the relay on this car is like the one on my Dakota. The EEC provides a switched ground signal(orange wire) to the relay. With out the signal, the circuit is open with no ground so the relay is open. As soon as ground is applied, the relay closes. If this is the case, then the fan will only work with the manual switch when the ignition is on just like my truck is. So, this actually makes wiring in the switch a whole lot easier. All you have to do now is run a wire from the switch to the orange wire on relay, then another wire from the switch to ground. When the switch is on, it will complete the circuit and the relay will close turning the fan on. Now, instead of having to try and find a 12VDC source under the dash, you just have to find a place for ground. This was the only thing I was unsure of when I posted because the EVTM I have is kinda vague on the operation of the circuit, and with my engine torn apart for head gaskets, I had no way to apply power to the relay to verify it worked properly. Thanks for doing the homework for me and helping to clear this up.
 
CaifanSC said:
im assuming you are tapping into the orange wire going into the relay...if im not mistaking that pin will act a certain way when the relay is receiving a 12v in put (ignition) and a different way when its not. Thats probably why you can have the fan work with 12v sometimes and sometimes with ground. If you are going to add a 12v input to have the fan run, do it to the dark blue wire which brings power to the fan its self..but use an inline fuse. I opted to do this at the fan (add power to the fan directly) and put the ground to the switch...just to complete the circuit. Definatelly check out the local boards man..we have a good following of tbirds...and more and more SC's are surfacing. There are plans to go to the track on the 8th...close to you...mason dixon dragway in hagerstown.
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The only problem with tapping into the actual power wire for the fan is you need to use a good guage wire(at least 12 guage IMO) and a decent fuse of at least 30 amps. Then you will NOT want to route power directly through a switch to the fan. If the switch fails or shorts, you are just asking for an electrical fire. Most switches aren't rated to handle the power the fan will draw for extended periods of time. To do it this way effectively, you need to hook up a seperate relay rated higher than the fuse you are going to use. Since you said you kept blowing 20 amp fuses and now use a 30 amp fuse, this means you will want at least a 40 amp relay or you will eventually kill the relay depending on how much you use the fan. I already have one manual switch on my car for the intercooler fan, and plan on using the same switch to turn on the pusher fan. I will just have to re-route my wires to the intercooler fan relay now to make it a switched ground so it will work.
 
Ok, well i just had to slap out the EVTM again....HSKR, you are correct. I checked the pinout page for the EEC and the orange wire is indeed a ground pin only used on our SC's. I checked where the REd wire was coming from and it comes from the IRCM not the EEC and it has 12v power once the ignition is turned on...so as you said, the relay is closed when the ground is completed by the EEC through the orange wire. For some reason I missed that while I was wiring...i might have to re-do mi wiring just to cut down on the wires I used.
 
Or if you want the fan to run anytime the ignition is on, and don't want to worry about a switch, you can just cut the orange wire and hook it straight to ground. Then, as soon as you start your car the fan will come on, and when you shut it off the fan will shut off. Personally, I'll stick to the manual switch because I don't think the fan will hlep much when you are cruising on the freeway so you can turn it off to take some load off the alternator.
 
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