Lightn95

I'm sure this has been asked a hundred times but I can't find the answer..

I did the LT1 swap.com harness conversion. For some reason I didn't add a pin to the Blue 42 for a fan control.... but I did add a pin to Green 33 for the 2nd fan control.
My question is, do I need both pins to control the fans? Does the Ecu need B42 and G33 to trigger the fan? Are they both Ground triggered? I'm only using 1 fan, so I'm hoping I can use G33 as a ground trigger through the Ecu for the relay and be done.

what do you guys think?

LetsTurboSomething

you only need one in practice. It provides ground for the 50amp fan relay. One of the pins is for the low temp fan and one if for the high temp fan. You can change the settings for each in hptuners to what ever you want. I use just the one to trigger two fans because I make to much heat and a low temp fan was pointless.

67Skylark

It would also depend the fan you choose. If you have a two speed fan it allows you to take advantage of the proper speed for conditions. I'm running a 95 Ford Taurus (Dorman Part number 620-101) in my 67 GM A-Body driven around Florida and found I very rarely need high speed.