Well, I am not an electral engineer, but I put the neg lead on the neg terminal and the red lead on the positive terminal, got 12.56 volts. Fair enough. But then I kept the neg lead on the neg terminal and the red lead on the negative clamp while it was disconnected and guess what, it reads 12.55 volts. I put the red lead on the alt pos, neg on battery neg, 0 volts. Put the red on the fan relay, neg on batt neg, 0 volts. What the hell?
