Well I made a 05+ style harness for a set of LS1 fans got everything hooked up and thought all was well but my coolant temp gauge worked for a little while and then just drop to 0. I unplugged the 33 pin I think well the green connector pin and it solved the problem. So I was just going to hook up the wire to the ac wire like the nelson harness and the fans came on with the key off. Well I unhooked that as it was late and this morning going to work the a/c controls were messed up the position selector and the a/c buttons would not work. I already checked all the fuses and even unhooked the fans as well as checking the pins to see if they were plugged in right. So anyone know what might have happened? Sorry for the long post just need to get everything working.

 

I would double check all plugs on the harness. Double check the spot were you wired into the ac. KySilverado recently did a writeup about his E-fan install. It's basically the exact setup that I used on my instal and it works great.
https://www.performancetrucks.net/fo...d.php?t=436041
I would stay away from using your ac as a trigger and have you PCM tuned to use the two pins (33 & 42), since the pins are empty.

 

If you made the harness to an 05 and then hooked it up to the AC line like the nelson harness you may have fried something. PCM outputs. It isn't wired to accept + voltage to trigger anything.

I suspect your harness wasn't wired correctly from the get go. The temp gauge going screwy while it was hooked up.

 

Well on my harness I tested it before I plugged it into the pcm by grounding the pins to makes sure everything would come on as it should and all was well. I can jump the a/c clutch relay and hear the clutch engage on the compressor just the inside controls are not responding. Is there any switches/ sensors I could test to see if they are messed up?

 

i used the nelson harness and tapped into the wrong green wire. the ac didnt work for a month tilli changed that tap. if i remember right there was a green wire and a green wire with a white stripe

 

I guess I will check out the green wire tomorrow and make sure it is not cut and still has power and the grn/wht is still grounded.

 

Got the ac workin this morning going to go over my harness sometime tonight or tomorrow and see if i cant get the fans workin on both pins.

 

Well made a new harness with some new relays and all is well this go around. Not sure what I did but I can control both fans with the pcm now.