nelson harness question
08-15-2010, 03:56 PM
#1
nelson harness question
Okay so i picked up a set of factory 05+ efans and a used nelson harness from another member on the site who had never installed them on his truck so he didnt have much of an answer for me. Every set instructions on the nelson harnesses that i can find say there is supposed to be 2 pcm pin wires (green and blue) of which the blue wire is supposed to go to pin 33 on the green plug and the green wire to pin 42 of the blue plug. Thats all fine and great except for the fact that the harness i got has a blue wire and a purple wire that go to the pcm...? Has anyone else had this problem and which wire is supposed to go to which pin on the pcm? Right now i have the blue wire the green #33 and the purple wire to blue #42, they seem to be working somewhat properly but my ac randomly blows completely hot air and the fans seems like they are coming on too late. thanks in advance guys.
Zach
Zach
08-16-2010, 09:06 AM
#3
If you truely have the Nelson harness it is not made to control the fan on for AC thru the PCM.
It turns on fan for AC by tapping into the AC trigger wire.
The nelson harness only has one wire going into PCM
It turns on fan for AC by tapping into the AC trigger wire.
The nelson harness only has one wire going into PCM
08-16-2010, 09:31 AM
#4
1 blue wire goes to the #42 pin of the pcm. the other goes to the pressure side of the AC compressor so when you turn the AC on it will turn the fans to High vs leaving the fans on low.
i can double check anything you need when i get off, i have the NP efan harness in my W/T.
08-16-2010, 12:29 PM
#5
If that is how the nelson harness is set up then why did both wires (blue and purple) both have pcm pins on the ends of the wires? Perhaps the harness i have isnt a Nelson harness at all and the guy i bought the fans from didnt know it wasnt a Nelson harness. The only thing im going off of is that i was told it was a Nelson harness. It has 2 power wires, two ground wires and two pcm wires, purple and blue. Also has the three relays on it and looks damn near identical to the pictures i could find of the Nelson harness. I just want to make sure everything is hooked up correctly and the fans are operating like they should. Thanks for the help guys, please chime in with any other info...really dont want to screw anything up with them
Zach
Zach
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