2004 Yukon efan conversion no tune - MacGyvered

[hutch8122]

(SOLVED)
New to the forum so.please forgive that I couldn't find a way to ask this in the thread I found on this topic. I have an 04 Yukon and dual efans from 05 Silverado with stock wiring harness and got the relay for the temp probe. Pin 86 white wire on the relay goes to the a/c comp relay but I am unsure as to which color wire/pin ....all videos say dark green wire but I have two same color green on the underside of the fuse box one for pin 85 in green/white stripe and I think that's the one but not sure. Any help is appreciated

 

[Marky Dissod]

... couldn't find a way to ask this in the thread I found on this topic.

Link please?
Maybe it said something wrong, or left something out?

One thing I can guess by looking at the title and then reading your post is that you never told your pcm to operate efans.
The pcm tune in every GMT800 from '99-'04 expects a mech clutch fan, meaning it is clueless about what you've done.
In other words, you may have already done everything ELSE right, and you now only have one step left: get tuned.

 

[hutch8122]

Link please?
Maybe it said something wrong, or left something out?

One thing I can guess by looking at the title and then reading your post is that you never told your pcm to operate efans.
The pcm tune in every GMT800 from '99-'04 expects a mech clutch fan, meaning it is clueless about what you've done.
In other words, you may have already done everything ELSE right, and you now only have one step left: get tune

I apologize, I am not tuning the PCM I'm using a temp.probe into the radiator and I am trying to confirm if I tie the white wire from this relay here to the green/white wire from under the fuse box as shown in pics or the dark green one to.the left of my finger

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please. If we can't see it, it does not exist.

You can obtain wiring diagrams for your truck at www.charm.li , and maybe you will find more information on the wires and pins that you are looking for.

 

[hutch8122]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please. If we can't see it, it does not exist.

You can obtain wiring diagrams for your truck at www.charm.li , and maybe you will find more information on the wires and pins that you are looking for.

I added pics to my reply

 

[Marky Dissod]

I apologize, I am not tuning the PCM ...

No apology to me applies.
That said, til you tune the pcm for a pair of electrical fans, even with perfect wiring (someone else wired it up for me), the pcm cannot operate your fans.

 

[afpj]

@hutch8122, are you thinking that the fans will turn on with just the temp probe as a trigger? I'm not sure it works that way.

 

[hutch8122]

(SOLVED)
I wired up the factory wire harness from a 05 Silverado and used the probe into the radiator so when the truck hits op temp the fans kick on low , used another relay and tied into the ac comp.relay pin 87 so when I turn on AC both fans run on high. All is working except after I turn off the truck the fans come on a few times for a min or two due to wiring it to constant 12v I'll add another relay tomorrow and run it to ignition power and that should fix the fans to only come on when the trucks on. Thanks all

 

[Joseph Garcia]

If your project is fully completed without issues after your next relay installation, please add the word "FIXED" or "SOLVED" to your thread's title, to let others who are experiencing a similar planned project know that this thread has an identified solution.