EZ Wiring Mini 20 Circuit Installation
Done some more voltage drop testing ....................
BAT+ to Blue field lead alternator: 0.76~78V
BAT+ to Blue VR plug: 0.62V
BAT+ to Blue IGN on ballast 0.58V
I took reading as high as 18~19V when the engine was running, not good. .
The single most important reading you took was at the regulator plug, but I assume you took that with the regulator UNhooked? This will falsely LOWER the reading, because the regulator and alternator field will no longer be drawing current.
With everything hooked up "normal," your readings at the ballast (key side) and the blue alternator field should be near the same. They are essentially the same wire.
BUT..................
The worst reading you took was at the alternator field............. .78V
Let's assume that the regulator CORRECTLY regulates at nominal 14V. Let's assume that that .78 appears at the regulator IGN terminal. This .78 would be ADDED to that 14, so even at that your charging voltage should only be 14.78--15, somewhat high, but certainly not the 18 you are experiencing.
So far as CURING the voltage drop problem, an underhood relay would be one solution.
And you seem to have checked out the regulator ground
The only two things left are (in some cases) a bad battery
or a bad regulator.
