First question. Why do my 12 volt lights get brighter when I plug into shore power? Next question is if I tap into my 12 volt reading light in the bedroom can I use those wires to run a pig tail to in...
Lights get stronger when you plug in because the battery charger is supplying your 12VDC, not the batteries. You probably have weak batteries or bad connections in the 12VDC side of things.