Dear Dennis, David and Alex;

This was great.  I have no idea what those laws are (I am a social scientist by profession, this is all new to me), but I look forward to learning more.

In the meantime, I attached a 4 AWG cable from the ground of the accessory battery (which is under the back seat) through the rear panel and to the frame.  Presto, problem solved.  I still don't know why or how, but I will do some reading.

Now, the complete accessory setup looks like this, I have the 4 awg ground to the chassis, a 6 AWG + cable to the accessory bus under the driver seat, plus a 6 AWG ground to the same bus. Jay Brown suggested I would need at least 6awg to that bus if I want to put headlights on it (which I have not done yet).  I also have a small bus on the cabinet panel opposite the water tank and moving accessories in the back (water pump, plugs and rear lights) to that bus to eliminate some of the wires going forward.

Thanks again.  Come to Boise and I'll buy the beer.

Dave B
Boise
________________________________
From: David Beierl <dbeierl@gmail.com>
Sent: Saturday, July 13, 2019 8:55 AM
To: David Boan
Cc: vanagonlist a; alex@mevay.org
Subject: Re: Finding a short

What Alex said.  You have an open ground on the house battery.  As soon as you connect a load to it the positive terminal floats at chassis ground level, and the negative battery terminal is now -12V to chassis.

Yrs,
d

On Fri, Jul 12, 2019 at 2:03 PM David Boan <dboan@outlook.com<mailto:dboan@outlook.com>> wrote:
I am working on correcting a short in my accessory wiring, and while making progress I have hit a plateau.  I thought someone might have experienced this and could save me much time searching ...