OK now that I have read it again......and again......I am thinking they left out a ground. I;m guessing the meter lights use a single power wire and simply connect to the chassis on the other side. Sounds like that jack should have been connected to chassis ground. Both + and - wires from the jack go to the circuit board I am guessing. Crap like this is hard to solve unless you have hands on then sometimes five minutes and a multimeter will solve it.It's connected to the same power supply that powers my radio. The cord is absolutely good, no issues with it at all. There's power inside the meter all over the place, except for the light bulbs. And all I had to do was run the negative from the jack in the back of the meter down to the case. Problem solved