anytime it something electrical, start with the most simple stupid problem first just to make sure its right. I have been wiring cars for almost 20 yrs now and just this week I found a simple/stupid problem that I really should have checked first, the old "check your grounds". I installed a dual battery system and at the heart of it is a isolating relay. I installed a switch this weekend so that I could use both batteries to start the car when I wanted/needed but after install I was suprised to see it was not working. After further inspection I discovered it has not been working since I installed it I tried to manually turn the relay on by simply jumping power from the power lug on top to the coil lug right next to it and nothing happened. The ground side of the coil was a 6" long wire with clear insulation that I personally crimped gold spade terminals on connected to a ground buss-bar I installed and have both batteries connected too. I never checked it because I could see the wire, literally through the insulation and the crimps and visually it looked perfect but when I put a temp wire next to it, connected to the same buss-bar suddenly I could hear it turning on. I took the wire off and tested it with my meter for continuity and it showed up as an open circuit. Tested it for resistance and it showed up as 151k ohms, didn't make any sence.... Today I cut the insulation on the wire and discovered that the wires right next to one crimp had broken and there were only two little strands that were still connected inside it. Through the insulation it still visually looked perfect but electrically it was as if it were not there. I spent a couple of hours first trouble shooting my switch install and other stuff before I just happened to check my ground.
first rule - check your ground..........
