Ford Windstar E-fan with LS Wiring

[cebra]

I have searched for hours on this and find similar threads even one title Ford Windstar E-fan wiring but it is showing a off/on type fan. Here is what I have:

LS with Standalone Harness: 2 wires (Lo and Hi)
Ford Windstar E-fan: 3 wires (blue/blk/blk) on each fan; I assume this is Lo/High/Ground in some order

I am trying to figure out how to wire relays for 3-prong fans, I see a ton of information on 2 prong dual fans. To add more complexity, I will be adding vintage air in a few months and will need to wire a trinary in as well. I found this and it is the simplest I have seen but for dual 2-prong fans.

[Clyde65]

They pull a TON of amps when they start! This was the only reason I desired against them.
The ones I have pull about 35amps at start up, through a relay like you.
I got them from Champion Radiator


Mine is also set up with a trinary switch so AC triggers also

[homemade87]

Originally Posted by cebra

I have searched for hours on this and find similar threads even one title Ford Windstar E-fan wiring but it is showing a off/on type fan. Here is what I have:

LS with Standalone Harness: 2 wires (Lo and Hi)
Ford Windstar E-fan: 3 wires (blue/blk/blk) on each fan; I assume this is Lo/High/Ground in some order

I am trying to figure out how to wire relays for 3-prong fans, I see a ton of information on 2 prong dual fans. To add more complexity, I will be adding vintage air in a few months and will need to wire a trinary in as well. I found this and it is the simplest I have seen but for dual 2-prong fans.

No need to wire the low speed wire on the fans . The 3 relay system will run both fans in series and will run at half speed for low speed . When the pcm commands high speed it will switch the relay and both will run on high . This is the reason for the 3 relays . Other wise you will only need 2 relays and wire in the low speed wire as well . It can done either way being you have a 3 wire fan .

As for a/c trinary for the fans . Nothing will be different for the fans if you wire it in the pcm like gm did , which I recommend .

[cebra]

That helps a lot, thanks so much. Do I just use the blue wire for power and the black for ground and leave the other black for nothing then?

[cebra]

I found this on LS1Tech and I think it is the way I will want to go...

[cebra]

I am going with the 3 relay method such as below. From what I can deduct the 3 gray wires are the power wires to the fans so I should use heavy gauge wire (like 10 gauge). The 2 blues and 1 black are the grounds and I can just use like an 18 gauge black wire for these. Just want to make sure I have this correct in my head so I don't run a small wire for a power wire.

[87chevy.com]

Originally Posted by cebra

I am going with the 3 relay method such as below. From what I can deduct the 3 gray wires are the power wires to the fans so I should use heavy gauge wire (like 10 gauge). The 2 blues and 1 black are the grounds and I can just use like an 18 gauge black wire for these. Just want to make sure I have this correct in my head so I don't run a small wire for a power wire.

Nope, dont use 18 gauge for those. Your probably catch your truck on fire. 12ga in, 12ga out.. funny how people re draw factory schematics and make them confusing...

all wires for 87, 87a and 30 is 12 or 10 ga. 85/86 terminals is 20 ga