Question: LS3 fan control wire; power or ground?

[dhutton]

Originally Posted by Gmachine1911

I’m looking at purchasing the Entropy fan controller but I do not want to run their secondary temperature sensor. On my LS3 crate engine with the GMPP harness, does the single blue fan wire send 12 V or a ground signal? I’m sure. this has been covered in depth already but after numerous searches, it is evading me. Thanks!

You won’t get two speed fans if you don’t use their sensor.