All of us amazon drivers know the glowing amp light pretty well.
I've got an upgraded 55 amp volvo alternator on my car, but my voltimeter and amp light always shows that power levels drop to as low as 8 volts when I've got all my "evening rain" systems going (lights, fan, wipers).

Hasn't been too much of a problem, but the voltage is usually pretty low 8-10 volts with these systems on and never higher than 14 volts with them off.

I realize that I'm probaably seeing some loss due to the 40-year old fusebox, but I was surprised by what happened earlier this evening.

I have a battery cutoff knob on my negative terminal. I usually disconnect the battery to discourage theft and to keep the battery from going dead. I was idling the car and decide to disconnect the battery before I had shut the car off. Not surprisingly, when I diconnected the battery via the knob, the care kept on idling.
What is surprising is that when I got in to kill the ignition, I noticed the voltimeter reading 16 volt. It dropped to 12 when I ran my "evening rain" systems, and again dropped to 12-14 when I reconnected the battery. Repeating the disconnect gave me a 16 volt reading.

Is something wrong here??