Stingray 5 2007 with preamp problem

Hi Guys. I have a 2007 Stingray 5 H that came this week. When o did plug It I listened only the single coil tones variarion. I put off the switch to see If have something wrong and the Violet wire touched the volume pot the hum finished. So I tested the poles with a Key and the pickup worked normaly. I put a new wire from the soldering of the Violet wire to volume pot. O Just need to know If originaly have a wire coneccting the Violet wire and to where go this cable. Thanks for the help