How can i hardwire my Fan to always run
#1
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How can i hardwire my Fan to always run
i want to hard wire my fan to a toggle switch so i can control when its on or off. how do i do this? the cheapest easiest way possible (its a beater to the max haha)
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Re: How can i hardwire my Fan to always run
Are you talking about the radiator fan or blower? For the first one easiest would be to bypass existing circuit (it goes through ignition, some relay, and a fuse box i believe) and just run a couple of wires, one to the ground, the other from a power source to the fuse, then to the switch, then to the fan motor. That is the simplest circuit I can imagine.
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Re: How can i hardwire my Fan to always run
Are you talking about the radiator fan or blower? For the first one easiest would be to bypass existing circuit (it goes through ignition, some relay, and a fuse box i believe) and just run a couple of wires, one to the ground, the other from a power source to the fuse, then to the switch, then to the fan motor. That is the simplest circuit I can imagine.
#4
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Re: How can i hardwire my Fan to always run
Easiest and best way is to find the thermostat fan switch on the back of the block. There are two wires going to the fan switch (+ yellow/green and black -). Tap a wire into the + yellow/green wire and run it to a switch inside the cabin. Ground the other end of the switch and you now have a switch to turn on your fan whenever you want and the best part is that it will not interfere with normal fan operation.
The coolant temp fan switch on the back of the block is a low amperage sensor that when it gets to a certain temperature, it grounds out and triggers the factory relays which power the fan. The method I suggested uses this coolant fan switch to trigger the factory relays to power the fan. The idea is to manually ground out the sensor with a switch and use the factory relays to turn the fan on. The current used to power the fan still flows through the factory relays and not through this circuit, so there is no problem with the switch overheating. The fan will be powered using the factory relays etc. so there is no need for additional relays.
The purpose of doing this allows the user to retain the functionality of the factory setup, as well as the option to turn on the fan in an emergency or in between runs.
The coolant temp fan switch on the back of the block is a low amperage sensor that when it gets to a certain temperature, it grounds out and triggers the factory relays which power the fan. The method I suggested uses this coolant fan switch to trigger the factory relays to power the fan. The idea is to manually ground out the sensor with a switch and use the factory relays to turn the fan on. The current used to power the fan still flows through the factory relays and not through this circuit, so there is no problem with the switch overheating. The fan will be powered using the factory relays etc. so there is no need for additional relays.
The purpose of doing this allows the user to retain the functionality of the factory setup, as well as the option to turn on the fan in an emergency or in between runs.
Last edited by gringo7718; 10-08-2012 at 03:48 PM.
#5
Re: How can i hardwire my Fan to always run
OP, why would you want to do this anyway? At high speeds, like highway, it'll overheat. I did this in the past because I ran a EG radiator, and anything over 75, the car would overheat. I just fixed it and put it back to normal and have had no problems since.
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Re: How can i hardwire my Fan to always run
Now to the op, I cut the ground wire for the fan right near the battery and just grounded it directly to the negative battery cable. I then took the positive wire and ran it into the cabin to the fuse panel under the dash, found a slot that was switched power and not in use and just used that to power it. Make sure you get a switch that can handle the amperage though cause mine tends to get hot if left on to long, that reminds me I still need to change that out haha.
#7
Re: How can i hardwire my Fan to always run
Well to be fair, mine wasn't ran on a switch, I went straight to the battery and unplugged it ghetto like every time I stopped at a place.
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#8
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Re: How can i hardwire my Fan to always run
The thermostat fan switch turns on the fan and uses low amperage. By doing what I suggested, you still retain all of the factory relays to power the fan at the correct amperage etc. It is really easy to use a switch, tap one wire into the + wire of the coolant thermostat switch, and the other to ground. This is well established as much safer, better, and easier than any other solution posted here.
Last edited by gringo7718; 03-26-2009 at 08:19 AM.
#9
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Re: How can i hardwire my Fan to always run
easiest and best way is to find the coolant temp sensor on the back of the block. there are two wires going to it (yellow/green + and black -) tap a wire into the positive and run it to a switch inside the cabin. ground the other end of the switch and you now have a switch to turn it on and off at will.
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Re: How can i hardwire my Fan to always run
yea thanks gringo, i'm starting to over heat my b16 when i have the a/c on and i'm idle for 10 mins. kinda wack cause i bought a new thermo stat switch...
#12
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Re: How can i hardwire my Fan to always run
The thermostat fan switch turns on the fan and uses low amperage. By doing what I suggested, you still retain all of the factory relays to power the fan at the correct amperage etc. It is really easy to use a switch, tap one wire into the + wire of the coolant thermostat switch, and the other to ground. This is well established as much safer, better, and easier than any other solution posted here.
i am confused though as to why someone would want to do this.. if the fan switch and coolant system is functioning properly, you should never have a need to manually turn the fan on.
#13
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Re: How can i hardwire my Fan to always run
You wouldn't have the issue of the switch overheating if instead you hooked the fan up to battery voltage in the engine bay. then run a ground wire from one side of the fan switch into the car to your rocker switch. no worrying about shorting anything out or overheating a switch if its only connecting a ground.
I will try to clarify this again so you can understand. The coolant temp fan switch on the back of the block is a low amperage sensor that when it gets to a certain temperature, it grounds out and triggers the factory relays which power the fan. The method I suggested uses this coolant fan switch to trigger the factory relays to power the fan. The current used to power the fan still flows through the factory relays and not through this circuit, so there is no problem with the switch overheating.
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Re: How can i hardwire my Fan to always run
weird thred i bought my rex alreay wired up with is being attached to the igniton kinda dumb but w/e i rewired so it works propery back on the coolant temp switch
in confused as to why you guys do this the point of the collant switch is so it tunrs on when needs if you havea switch in your car you dont really know exactly when to turn it on precisly when the engine needs/wants it
in my opinion kinda eleminates the point of "engine-rad-fan-cooling"
if some one could explain what the real purpose is and how it affects things that would be good just doesnt seem really logical
in confused as to why you guys do this the point of the collant switch is so it tunrs on when needs if you havea switch in your car you dont really know exactly when to turn it on precisly when the engine needs/wants it
in my opinion kinda eleminates the point of "engine-rad-fan-cooling"
if some one could explain what the real purpose is and how it affects things that would be good just doesnt seem really logical
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Re: How can i hardwire my Fan to always run
[QUOTE=blazzer;38956297
if some one could explain what the real purpose is and how it affects things that would be good just doesnt seem really logical[/QUOTE]
In case of an emergency overheat your car can still make it home.
if some one could explain what the real purpose is and how it affects things that would be good just doesnt seem really logical[/QUOTE]
In case of an emergency overheat your car can still make it home.
#17
Re: How can i hardwire my Fan to always run
weird thred i bought my rex alreay wired up with is being attached to the igniton kinda dumb but w/e i rewired so it works propery back on the coolant temp switch
in confused as to why you guys do this the point of the collant switch is so it tunrs on when needs if you havea switch in your car you dont really know exactly when to turn it on precisly when the engine needs/wants it
in my opinion kinda eleminates the point of "engine-rad-fan-cooling"
if some one could explain what the real purpose is and how it affects things that would be good just doesnt seem really logical
in confused as to why you guys do this the point of the collant switch is so it tunrs on when needs if you havea switch in your car you dont really know exactly when to turn it on precisly when the engine needs/wants it
in my opinion kinda eleminates the point of "engine-rad-fan-cooling"
if some one could explain what the real purpose is and how it affects things that would be good just doesnt seem really logical
Spoon and Mugen thermo switches are located were the oem is located and they are low temp, they turn on @ a lower degree for cooling purposes. I'm not sure how it will effect the car but i see that there is going to be more energy and volt generated from the fan being on.
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Re: How can i hardwire my Fan to always run
i'm still at a loss as to why you would want to bypass the fan relay if all is working as it should? i mean, honda put that there for a reason. if it doesn't work, try changing the relay, or temp sensor. if it aint broke, don't fix it!
#20
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Re: How can i hardwire my Fan to always run
You completely missed what is happening here. Who ever said anything about my switch overheating???
I will try to clarify this again so you can understand. The coolant temp fan switch on the back of the block is a low amperage sensor that when it gets to a certain temperature, it grounds out and triggers the factory relays which power the fan. The method I suggested uses this coolant fan switch to trigger the factory relays to power the fan. The current used to power the fan still flows through the factory relays and not through this circuit, so there is no problem with the switch overheating.
I will try to clarify this again so you can understand. The coolant temp fan switch on the back of the block is a low amperage sensor that when it gets to a certain temperature, it grounds out and triggers the factory relays which power the fan. The method I suggested uses this coolant fan switch to trigger the factory relays to power the fan. The current used to power the fan still flows through the factory relays and not through this circuit, so there is no problem with the switch overheating.
i was replying to hondacivic90zc's post, #6, not yours.
#21
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Re: How can i hardwire my Fan to always run
The thermostat fan switch turns on the fan and uses low amperage. By doing what I suggested, you still retain all of the factory relays to power the fan at the correct amperage etc. It is really easy to use a switch, tap one wire into the + wire of the coolant thermostat switch, and the other to ground. This is well established as much safer, better, and easier than any other solution posted here.
However, I rarely use my fan because normal driving will cool the motor by itself... The only time I really use it is during traffic and that's the time when I see the temperature gauge go up slowly....
#22
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Re: How can i hardwire my Fan to always run
I have mine wired up like so. I cut off the sensor plug that goes to the thermostat which (we all know activates the fan when the sensor reaches a certain temp) and ran the two wires to the cabin to a switch. Turn the switch on and the fan activates. I see no problem with this set up.
#23
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Re: How can i hardwire my Fan to always run
bad idea to just use a switch...something could melt and catch fire.
at least use those wires on the engine temp switch. then it is running thru the proper relay and fuse. it's just as easy or easier, if you HAVE to have a switch.
personally, the stock setup is the way to go
at least use those wires on the engine temp switch. then it is running thru the proper relay and fuse. it's just as easy or easier, if you HAVE to have a switch.
personally, the stock setup is the way to go
#24
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Re: How can i hardwire my Fan to always run
bad idea to just use a switch...something could melt and catch fire.
at least use those wires on the engine temp switch. then it is running thru the proper relay and fuse. it's just as easy or easier, if you HAVE to have a switch.
personally, the stock setup is the way to go
at least use those wires on the engine temp switch. then it is running thru the proper relay and fuse. it's just as easy or easier, if you HAVE to have a switch.
personally, the stock setup is the way to go
#25
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Re: How can i hardwire my Fan to always run
it's best to leave it stock, or change your coolant temp sensor or just repair the wires because i have a feeling you want to do this because something is wrong
it's best to leave it stock, for two reasons:
1: you're not paying attention the gauge, and it overheats, your head's screwed and maybe your block too
2: if it's always on your car will run rich, because of the same reasons it does when you don't run a thermostat, the engine won't reach normal operating temp, and the computer will keep dumping fuel in an effort to heat it up
it's best to leave it stock, for two reasons:
1: you're not paying attention the gauge, and it overheats, your head's screwed and maybe your block too
2: if it's always on your car will run rich, because of the same reasons it does when you don't run a thermostat, the engine won't reach normal operating temp, and the computer will keep dumping fuel in an effort to heat it up