While assembling mods I have on occasion inadvertently allowed the wire connected to the Luxeon's positive (that's positive) lead to touch, just for a split second, a heatsink or some other grounded surface, at which time the Luxeon became instantly, as well as very permanently, inoperable. But if you have a 6D Mag, I doubt this is the case since the reflector is only made of non-conductive plastic, plus you mention it was the negative lead anyway which should already be grounded. Hopefully it's just a loose wire due to the heavy weight, and the inherent problems associated with anything of great size and mass...