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A gentleman never tells but I’m just looking at electric fan controllers for my car. I have a deralle adjustable one right now and the concern I have with it is that it stays on and attempt to cool my car until it gets to the correct temperature and it’s killing my battery. So im looking for one preferably the same style but one that shuts off and stops blowing air when I **** my car down. If someone will recommend me some that do that, that would be super nice of you. Thanks!
 

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It sounds like your controller is wired incorrectly and using a constant 12 volt circuit. You should be connecting to a switched/ignition hot circuit to shut your fans down when the engine stops.

Rusty
 

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Actually I'd like to wire it that way. I think I may know how after thinking about it but i'm unsure. My guess is that instead of wiring it to the positive battery terminal like it said in the instructions to do, I should wire it to my solenoid positive. Am I correct? Or am I off? You tell me. It's a Derale 16769.
 

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These instructions don’t mention attaching to the positive terminal of the battery. https://derale.com/images/stories/virtuemart/product/pdfs/16769.pdf

Personally I would use that controller to trigger a relay that gets fan power from the battery. Those instructions want you to find a switch 12 volt wire to power your fan, when a relay would be the better way.

Rusty
 

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The positive side of the starter solenoid is also a constant hot location so you don't want to use that. There is not a switched ignition hot lead inside the engine compartment that is a heavy enough gauge of wire to safely run an electric fan. That is why you need a kit that has a relay for the hot to fan lead.

I am partial to painless performance for stuff like this and I have one of theirs that has a water proof cover for the relay. You will need a location on the intake manifold to screw in the thermostat.
 

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I always run a "key on" solenoid to energize a terminal bar that runs anything requiring key on 12v ie. electric fan(s), electronic ignition, tach, stereo, etc. Search Ford Muscle keen on 12 volts key on.
 

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If you have an electric choke, it is powered as a switched 12v. You could use the source of your electric choke to also trigger the relay that would switch the current power source you're using to run your fans. If you're not to familiar with relays, it has two circuits. One circuit for the load, which for you would be your fans. And the other circuit for the relay switch. The load circuit is input on pin 30 and output on pin 87. The relay switch circuit are pins 85 and 86 which are not polar. So you could connect pin 85 to a good steady ground and you could connect the electric choke feed to pin 86.
 

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The positive side of the starter solenoid is also a constant hot location so you don't want to use that. There is not a switched ignition hot lead inside the engine compartment that is a heavy enough gauge of wire to safely run an electric fan. That is why you need a kit that has a relay for the hot to fan lead.

I am partial to painless performance for stuff like this and I have one of theirs that has a water proof cover for the relay. You will need a location on the intake manifold to screw in the thermostat.
I want to know also.
See attached photo of Starter relay.
Would you attach the relay signal from terminal #1 or #2 of the starter relay, going to terminal #85 on the relay? (is one of those numbered on the starter relay switched?) (...with heavy duty wire coming from battery to terminal 30 on the relay)

Starter Relay.jpg
 

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I honestly don't know why people use fan controllers at all? It is much simpler to use an in-line temp switch to trigger a relay to turn the fan on and off. The only trick to that approach is you have to have somewhere to install the switch. I suppose a controller might be worth it if you are trying to run the fan at different speeds....but why bother with that at all? Running a fan at max still provides 150k+ miles of fan life.
 

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Neither. The wire attached to terminal 1 is only energized when you want the starter motor to spin.
The POST labeled terminal 2 has 12 volts on it only while you want the starter motor to spin. (this provides full 12 volt to the ignition during starting)
The WIRE attached to terminal 2. is connected to the same wire that feeds the ignition points. It has reduced voltage because of the pink resistor wire.

NONE of these are appropriate to provide 12 volts to trigger your relay
 

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I honestly don't know why people use fan controllers at all? It is much simpler to use an in-line temp switch to trigger a relay to turn the fan on and off. The only trick to that approach is you have to have somewhere to install the switch. I suppose a controller might be worth it if you are trying to run the fan at different speeds....but why bother with that at all? Running a fan at max still provides 150k+ miles of fan life.
IMO one good reason is to avoid the large inrush Current some fans draw when starting. It will also draw less when full speed isn't required. I would always have a method of bypassing the controller in case of failure though. Even if it's just a jumper wire !
 

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How long is your fan running after you shut off the engine? A minute or so after you shut off the engine is normal- and IMO- a good idea. But if it is running so long that it drains the battery either the controller is defective or it is wired incorrectly.
 

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Most controllers don't have an off-delay timer, that would have to be added. Running them after shutoff isn't a bad idea, but even my Boxster kills the engine compartment fans when the key is off.
 

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Neither. The wire attached to terminal 1 is only energized when you want the starter motor to spin.
The POST labeled terminal 2 has 12 volts on it only while you want the starter motor to spin. (this provides full 12 volt to the ignition during starting)
The WIRE attached to terminal 2. is connected to the same wire that feeds the ignition points. It has reduced voltage because of the pink resistor wire.

NONE of these are appropriate to provide 12 volts to trigger your relay
Thanks. So is there a nearby location by the radiator for an "ignition on" (key on) connection to actuate the fan relay?
 

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I installed an electric fan and a Mishimoto fan controller into my 65 Converter. The wiring is very similar to this diagram. I made a few changes by placing the fuse in-between the battery and fan. I also went with an NPT temp sensor rather than a radiator probe style sensor. I wired the green override wire into the air conditioning compressor so that if the AC is on, the fan will pull air through the condenser even if the engine isn't up to standard operating temperature. The control module is wired into the ignition so the fan will not run when ignition is off. However, I can run the fan when the ignition switch is turned to accessory. There are many different ways to go about this, but I also like this particular control module since it can be adjusted to turn on and off at different temeperatures.

761428


761429
 

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Electric choke
Rufus,
Are you saying that the terminal for the electric choke is hot when the ignition is on?
Well, I traced the choke wire, and it goes to the "LEFT" small terminal on my Starter relay. CLEARLY, I am confused -- shouldn't the electric choke wire be "on" all the time that the key is on?
If so, it seems that I should be able to use it for my fan circuit to engergize the fan relay, no?

But what ASM109 says makes sense -- that same terminal should only be hot when the starter needs to be engaged, so should not have current running thru it all the time the key is on........
Arggh
 

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My Derale controller had a yellow wire that can be connected directly to the battery/solenoid so the fan can run with the car off OR connected to switched power from the ignition so it can only run with the car on.
 
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