fan switch

Hello fellow Beetle brothers an sisters, First my name is Allen an i am new to the VW World. I have a 2001 VW Beetle 1.8T Gas 5 Speed manual trans. Problem that has my head spinning an looking for the correct answers. I have been all over the forms an see the same issues just need pointers...

I have a situation with my cooling system. Both fans come on when straight wired, and when I jump the fan thermo switch on the radiator the high speed fan setting works properly. When I jump the other wire nothing comes on. I am replacing the thermo fan switch and need to know what else could...