Hey, i got a hypertech to cal. my new tires untill i can get me a custom tune. I noticied that it has an option where you can set the computer to turn on and off electric fans, my truck now has no electric fans, but i am about to purchase some ls1 fans and harness from someone off this web site, my question is once i get the fans in and the harness connected to the computer should it cut the fans on and off like i want. ( after i program it to)

 

It is my understanding that option only works if you have electric fans from the factory or you have a custom tuner (not a handheld) turn on that feature. Supposedly someone with a GM Tech 2 can do it too. But a handheld alone will not turn on that feature.

someone correct me if i am wrong.

 

I believe that you are right, techII or custom tuning software. I do not think that a handheld can enable that function in the PCM rather it may be able to change it if factory enabled.