bigfatls6

iTrader: (34)

ive been working on wiring up the cooling fans on my 1970 ls swaped nova and from the way it looks on my PSI harness instructions you use the dark green and dark blue wires from the harness to switch the grounds to the coils on the relays to turn the fans on and off. for some reason it will not work. I don't have a ground on either of the 2 the dark green or blue wires. im just wondering what im missing here or if for some reason the computer is not doing what it is supposed to. I wired it in like it should be and tried turning the fans on with my hp tuners scanner but they didn't work. I could ground the relay and they would come right on.
if any one has a good drawing of how to wire in the relays for the cooling fans using the trigger wires from the computer please post it up.

kossuth

iTrader: (12)

Here is the C5 wiring diagram for the cooling fans. Fbody setups are the same. Hope this helps.

superbean

From LT1swap.com..

Hopefully this helps. PCM signals will be signal ground, opposite of that on relay will be 12v either switched or B+ but must be fused.

bustac

iTrader: (1)

Here's one I used that I found on one of the sites.