Auxiliary fan wiring

[VIKING_MECHANIC]

If there's a sticky or good post please point me that way, if not..

I bought a 10" auxiliary fan I will mount on the front of the AC condenser to help keep my engine koool while I'm in Texas. Question is, how do I wire it up?

I've seen videos on how to do this, but was curious to see what some of you guys did.

I also bought with the fan, a 4-pin relay, in line fuse holder, 6a toggle switch and 7.5 fuses(fan is rated at 5.45amps). I want the fan wired up to where is will only be on when I need it.

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[packer0440]

I know that the trucks that have these from the factory use a temp switch to activate the relay (closes around 230 degrees I want to say) If you want it to come on sooner then a toggle switch is probably a better choice though.

 

[Erin]

If there's a sticky or good post please point me that way, if not..

I bought a 10" auxiliary fan I will mount on the front of the AC condenser to help keep my engine koool while I'm in Texas. Question is, how do I wire it up?

I've seen videos on how to do this, but was curious to see what some of you guys did.

I also bought with the fan, a 4-pin relay, in line fuse holder, 6a toggle switch and 7.5 fuses(fan is rated at 5.45amps). I want the fan wired up to where is will only be on when I need it.

You must be registered for see images attach

Mine is wired to a switch on the dash. I just have to remember to turn it off when I turn the truck off. I left it on while fishing one time.

 

[Frank Enstein]

Tap into the wire that gets +12v on the A/C compressor and connect it to terminal 86 on the relay.

Ground terminal 85 on the relay.

Put the fuse holder as close to the battery as you can and connect that wire to terminal 30.

Connect the +12v side of the fan to terminal 87.

Ground the other wire from the fan.

*Caution, make sure the fan turns the correct way!*

 

[VIKING_MECHANIC]

Tap into the wire that gets +12v on the A/C compressor and connect it to terminal 86 on the relay.

Ground terminal 85 on the relay.

Put the fuse holder as close to the battery as you can and connect that wire to terminal 30.

Connect the +12v side of the fan to terminal 87.

Ground the other wire from the fan.

*Caution, make sure the fan turns the correct way!*

So would the fan get it's power from the compressor and would it be drawing current when the key is off?

 

[VIKING_MECHANIC]

Also, would a 4-pin relay work with the toggle switch or do i need the 5-pin?

 

[Frank Enstein]

The fan would only run when the relay is activated. The only the only thing the A/C clutch wire would power is the relay itself which is under 1 amp.

A 5 pin relay has an 87a terminal. That terminal is connected to terminal 30 when the relay is NOT activated.
You would use that for something you want to turn off by activating the relay.

An example is I wanted to turn off the headlight on my Yamaha when I hit the starter button so I ran the headlight power into terminal 30 and out of terminal 87a.

If you want a manual override so the fan runs without the a/c on, I recommend a second relay and switch the ground leg of the circuit through the manual switch to ground.

If you want to be able to prevent the fan from coming on with the a/c run the ground leg of the relay's terminal 85 (you won't need a second relay for this) through the manual switch so when the switch is "off" the fan will never run.

 

[Frank Enstein]

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[TacosnBeer]

you can easily do it yourself with the above or painless makes a prebuilt kit.... I got mine of Amazon, all the wires are labeled and comes with everything you need. just depends on how much you wanna spend. I chose the easy route with the painless kit

 

[Schurkey]

I also bought with the fan, a 4-pin relay, in line fuse holder, 6a toggle switch and 7.5 fuses(fan is rated at 5.45amps). I want the fan wired up to where is will only be on when I need it.

You must be registered for see images attach

Fan is rated at 5.5 amps. But what is the inrush current? May be much higher than the steady-running current draw. You may need a larger-capacity fuse.

If this was me, I'd put the fan on a self-resetting circuit breaker instead of a fuse. That, or a fusible link which will withstand short term overloads much better than a fuse.

Connecting the relay to the A/C compressor clutch power is a great idea. I'd have probably used a temperature probe in the cooling system, which would be more expensive and more messy.