When it comes to electrics I'm a real Bozo. The wires behind the control panel are a dogs breakfast. I don't have
much in the way of electrical components but what I do have are not working except for one weak LED cabin light.
So I put the multimteter to work and got 13.8 v across the bus bars. The negative bus bar does not seem to be the
common earth for the components, only for the switches ( which all work ). The live bus bar feeds the switches from
which a wire goes to the component, but where is the earth wire. The boats wiring is cast into the fibreglass
moulding of the boat so it's not exposed and I can't follow where it goes. Is each component earthed separately
or is there a common earth somewhere and if so where do I find it ??.