Electric Fan Wiring

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Justinhb

Justinhb

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Hi All,

I have been roaming around here, and the B and C body sites, but still can't seem to find the answer to my question. I am running the factory 318 in my '70 Duster, original auto trans, and wiring, with aftermarket A/C, and FiTech EFI. The FiTech EFI will be running the cut in and out of the new electric fan (also using the factory shroud). I am using the stock ballast resistor setup and jumping the wires with a terminal block to power the white wire for the FiTech EFI system.

The new fan uses the standard relay setup, but I am looking for a location to power the white 12v switched for the fan from under the hood? I am a visual guy, so photos of the wiring location would be the best if you have an idea. Thank you to everyone for your help in advance (including you veteran's out there!)!

As a side note I have read Golduster318s post, but it did not seem to help. :(
 
Justinhb said:
Hi All,

I have been roaming around here, and the B and C body sites, but still can't seem to find the answer to my question. I am running the factory 318 in my '70 Duster, original auto trans, and wiring, with aftermarket A/C, and FiTech EFI. The FiTech EFI will be running the cut in and out of the new electric fan (also using the factory shroud). I am using the stock ballast resistor setup and jumping the wires with a terminal block to power the white wire for the FiTech EFI system.

The new fan uses the standard relay setup, but I am looking for a location to power the white 12v switched for the fan from under the hood? I am a visual guy, so photos of the wiring location would be the best if you have an idea. Thank you to everyone for your help in advance (including you veteran's out there!)!

As a side note I have read Golduster318s post, but it did not seem to help. :(
Click to expand...
I don't have a fitech, mine is a fast 2.0, it has 2 trigger wires, fan #1, AND FAN #2, I USED FAN #1 TO TRIGGER A RELAY----------
 
72bluNblu said:
Have you seen the pdf file goldduster318 made?

https://www.forabodiesonly.com/mopar/attachments/electric-fan-26in-radiator-pdf.1715101084/

You also haven’t mentioned what fan you’re actually running. It makes a difference if it’s a single fan or a double, and if it has more than one speed.
Click to expand...
Hi,

Yes, I have read his post, and he used a fan controller, not the original harness like I am using.

I am running a single fan with a single speed, like a Spal...

Thanks for taking the time to reply...

JB
 
famous bob said:
I don't have a fitech, mine is a fast 2.0, it has 2 trigger wires, fan #1, AND FAN #2, I USED FAN #1 TO TRIGGER A RELAY----------
Click to expand...
Hi,

Thanks for taking the time to reply. I will use the Fitech to trigger the fan relay as well, but don't know where to run the white relay wire to on the factory harness...
 
My FiTech has a yellow wire that supplies the ground for the fan relay. The switched power I just jumped over to the main power feed on the relay.
 
MomsDuster said:
My FiTech has a yellow wire that supplies the ground for the fan relay. The switched power I just jumped over to the main power feed on the relay.
Click to expand...
Hi,

Thanks for responding...

I guess I am all screwed up, because I don't understand. My relay has four wires including a white wire that is supposed to go somewhere, but I don't know where. I was able to test the fan using the battery prior to installing it (it works) and have all of the other wires per the fitech diagram (blue, yellow, and red) but it is unclear where I need to connect the white wire...

Thanks again!
 
TrailBeast said:
You need a 12v switched ignition source then?
Click to expand...
Hi,

Thanks for taking the time to reply...

Yes, I believe so, but I spoke with Momsduster and he ran his with the red power wire to the battery and had no issues...
 
Justinhb said:
Hi,

Thanks for taking the time to reply...

Yes, I believe so, but I spoke with Momsduster and he ran his with the red power wire to the battery and had no issues...
Click to expand...

If your white wire can be wired direct to power that's probably fine, but since you said it was connected to the ballast wiring I have to think it needs to be switched.

No instructions with it?
Maybe look them up online if not?
 
If you don't have a wire around on the car there is no single good spot to pull power.

The battery is a decent spot when the car is not running, not so good when engine is running.
 
TrailBeast said:
If your white wire can be wired direct to power that's probably fine, but since you said it was connected to the ballast wiring I have to think it needs to be switched.

No instructions with it?
Maybe look them up online if not?
Click to expand...

Hi TB,

Thanks for the reply...

The white wire isn't connected to anything right now, hence the conundrum of where to wire it to. It isn't connected to the ballast. The instructions that came with the fan kit aren't the greatest...but I have them...it just says to wire it to a 12V switched source...
 
crackedback said:
If you don't have a wire around on the car there is no single good spot to pull power.

The battery is a decent spot when the car is not running, not so good when engine is running.
Click to expand...
Hi CB,

Thanks for responding...

I don't have a wire around...

I am surprised that I seem to be the only one that has had this issue, but given the options, I think am going to follow what Momsduster has done. He is running the same setup and hasn't had any issues, so I think that may be my best option...
 
Justinhb said:
Hi TB,

Thanks for the reply...

The white wire isn't connected to anything right now, hence the conundrum of where to wire it to. It isn't connected to the ballast. The instructions that came with the fan kit aren't the greatest...but I have them...it just says to wire it to a 12V switched source...
Click to expand...

Ok, sorry if I'm being annoying about this but I'm trying to figure out exactly what you are dealing with.
If it say's a "switched source" then you can go a few different places to get that power supply. (Your fuse box has an "Acc" fuse connection on the back of it)
There are blade terminal connections on the back side of the box at the "Acc" fuse, for one.
They look like this, but you need to make sure it's on the Acc fuse.

20150620_145335.jpg
 
It's not you, it's the car and the charging system design. If you hook power at the battery, you are running ALL the fan amperage through the bulkhead connector twice and ammeter (if still in system). That a POOR way to do it and it's the system routing that is the issue. Run a wire around and that will alliviate the issues.

People don't have problems with this stuff until things start melting and you have a disaster on your hands.
 
I think where the confusion starts is that there are (2) white wires he’s dealing with. One is the switched source for the FiTech that is connected to the ballast on the 12v side. The other is on the wiring to a standard Bosch style fan relay, and in his case is also a switched source. That is the wire that will be to the battery, (or jumped to main power at the relay), as the FiTech supplies the ground for the fan relay.
 
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MomsDuster said:
I think where the confusion starts is that there are (2) white wires he’s dealing with. One is the switched source for the FiTech that is connected to the ballast on the 12v side. The other is on the wiring to a standard Bosch style fan relay, and in his case is also a switched source. That is the wire that will be to the battery, (or jumped to main power at the relay), as the FiTech supplies the ground for the fan relay.
Click to expand...
And that's why I have typed then deleted 3 different replies here during the past 2 days. Majority of us can't know if Fitech/whatever supplies positive or negative signal to the fan relay coil.
So now we know this fan relay is wired just like a horn relay. Hot goes through the horn relay at all times. The horn switch in steering wheel provides a ground path to close the relay, horn blows.
If he has switched hot to Fitech/whatever that same switched hot can go to this white wire. Or he could use a hot at all times ( like the horn relay ).
I would likely add a inline fuse if I went that route. I just don't like hot at all times. I live with the ones she was born with but those are factory routed wires, most attached with nut and bolt terminals in engine bay. Bulkhead is the exception and we've seen how that works.
 
And after more thought, if the car had an electric choke you could use that wire for white wire on the relay verses going directly to the battery or jumping to the 12v main source.
 
MomsDuster said:
And after more thought, if the car had an electric choke you could use that wire for white wire on the relay verses going directly to the battery or jumping to the 12v main source.
Click to expand...
Yes, electric choke, spark ignition, voltage regulator, any blue wire in the engine bay is the same source, hot from ignition switch in on position.
 
MomsDuster said:
I think where the confusion starts is that there are (2) white wires he’s dealing with. One is the switched source for the FiTech that is connected to the ballast on the 12v side. The other is on the wiring to a standard Bosch style fan relay, and in his case is also a switched source. That is the wire that will be to the battery, (or jumped to main power at the relay), as the FiTech supplies the ground for the fan relay.
Click to expand...

Yea, I was thinking that was probably the case but didn't know about the ground switching part of the FI.
Getting clear information was a bit tough as well. :poke::D
 
TrailBeast said:
Yea, I was thinking that was probably the case but didn't know about the ground switching part of the FI.
Getting clear information was a bit tough as well. :poke::D
Click to expand...
I know it’s sometimes difficult for me to put thoughts into words on a screen. I don’t feel like I’m always being clear. That’s one reason I had him call me. It’s easier for me to explain that way sometimes.
 
If the relay #30 terminal is grabbing power at the battery with no wire around in place, that's a bad thing.
 
crackedback said:
If the relay #30 terminal is grabbing power at the battery with no wire around in place, that's a bad thing.
Click to expand...
I always forget that. So it would be better to run that power (#30) terminal fused directly to alternator, correct?
 
With a factory wiring system there is no good single solution. It's compromised by the charge routing through the bulkhead.

At alternator, good when engine is running, not so when off.
At battery, just the opposite.

That's why I suggest a wire around to bypass the bulkhead and ammeter with these types of add ons.
 
I bypass the ammeter and use my starter relay main power lug as my main power distribution point. It gets its main power from the 8 ga. wire from the battery. From there I connect to the following:

Alternator 8 ga (14 ga fusible link) provides more direct charge to batt and power to accessories
Ignition switch 10 ga (16 ga fusible link)
Fan Relays (in-line fuse holder)
A/C Relay (in-line fuse holder)
Headlight Relays (in-line fuse holder) relays are triggered by original headlight switch outputs hi/lo

This is how most modern vehicles are wired. It unloads the vulnerable bulkhead connector and ignition switch circuits. It also provides shorter path for battery charge and full power to your major power robbing items. I am running 130 amp alternator off a mid 80's Chrysler full size. Bolts right up and works with existing voltage regulator. You end up with a much more efficient electrical layout and bright white headlights as well.
 
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