2000 Blazer

[TribeamConnek 0]

I wanted to know if anyone else has had this problem yet.  Im working on a new build in a blazer everything is going well so far.  Im just trying to get the last part of my electrical straight before I build the enclosure.  I have a singer 350a alt and I decided to add a mechman vcm.  Everything has been hooked up properly but Im not getting any power to the vcm.  I checked over wires and made sure I was getting voltage and everything checks out fine.  I happened to notice that the plug which hooks up to the alt has one red wire.  The plug happens to have 4 prongs.  I wanted to know if that could be the reason for things not working as they should.