6v Battery wiring in 2004 Fleetwood Southwind

Thanks for getting back with the solution.

Hello all....Yep. Lesson learned on the whole photo thing. Will do that in the future, no matter how simple the task may be. The third cable that appeared to be a ground actually went to a 12v Relay that was tripped so when I ran the continuity test with the meter it showed up as a ground. I photographed the relay and had the guy from All Seasons Mobile RV in Apache Junction advise me on that. He is great. Have used him several times when I lived there over the last three winters. He took my call and helped out. All wired now. The cable that went to the 12v Relay switch got tied to the positive terminal. Thanks for the input on this issue. All comments are welcomed. .....John.

There is a "cheater's way" to assist with diagnosing a self-inflicted gunshot wound. You have I'd a definite positive and a definite connected to chassis negative cable. Two of the three.

I made up a 30 amp auto-reset circuit breaker tester lead. A breaker with two pigtails - one from each post. A foot or two length of wire (I chose 10-gauge cross-link wire). And two mean-ass electrical test lead clamps. One on each end. I used heat shrink (big stuff) over the breaker but it can be wrapped with electrical tape.

Now this breaker will do absolutely ZERO to protect against accidental reverse polarity mis-connection of the battery wires, but it does limit current to an unknown wire in case something weird happens.

NOW I PREACH...

All you younger folk have cell phones with cameras and tons of "selfies" and assorted digital images in memory. In the old days, I used to take dozens of images of an engine compartment, harnesses, underdash, the battery compartment, you name it, then rush to the local Costco store to get them developed. This saved my bacon so many times I lost track. The converter fuse area was nightmare incorporated.

It does little good to jabber this stuff to someone who has felt the effects of a mistake, but for crying out loud, when gathered together with other RV'ers mention the cell phone images trick. It really does work.

I did a 66 foot Chriss Craft yacht rehab in 1988 in which the original construction electrician ran over two thousand feet of white marine 3-conductor wire, unconnected at both ends then walked off the job. The bundle beneath the utilities console was thicker than my thigh. This can be referred to as "A Trial By Fire" Black, white and green wire inside the white jacket. Some of the circuits were D.C. using a separate ground meaning all three colors had the role of positive power leads. Paralleling AC with DC is horrible for noise induction. Thought I'd throw this own to lend a little perspective on what ID'ing a single wire means :)

There is a "cheater's way" to assist with diagnosing a self-inflicted gunshot wound. You have I'd a definite positive and a definite connected to chassis negative cable. Two of the three.

I made up a 30 amp auto-reset circuit breaker tester lead. A breaker with two pigtails - one from each post. A foot or two length of wire (I chose 10-gauge cross-link wire). And two mean-ass electrical test lead clamps. One on each end. I used heat shrink (big stuff) over the breaker but it can be wrapped with electrical tape.

Now this breaker will do absolutely ZERO to protect against accidental reverse polarity mis-connection of the battery wires, but it does limit current to an unknown wire in case something weird happens.

NOW I PREACH...

All you younger folk have cell phones with cameras and tons of "selfies" and assorted digital images in memory. In the old days, I used to take dozens of images of an engine compartment, harnesses, underdash, the battery compartment, you name it, then rush to the local Costco store to get them developed. This saved my bacon so many times I lost track. The converter fuse area was nightmare incorporated.

It does little good to jabber this stuff to someone who has felt the effects of a mistake, but for crying out loud, when gathered together with other RV'ers mention the cell phone images trick. It really does work.

I did a 66 foot Chriss Craft yacht rehab in 1988 in which the original construction electrician ran over two thousand feet of white marine 3-conductor wire, unconnected at both ends then walked off the job. The bundle beneath the utilities console was thicker than my thigh. This can be referred to as "A Trial By Fire" Black, white and green wire inside the white jacket. Some of the circuits were D.C. using a separate ground meaning all three colors had the role of positive power leads. Paralleling AC with DC is horrible for noise induction. Thought I'd throw this own to lend a little perspective on what ID'ing a single wire means :)

Can you trace the three wires to see what the other ends attach to?

Offhand, I would guess that one is the ground and connects to the chassis. One probably goes to the disconnect relay and the general house circuits, and possibly to some unswitched circuits. The final I would guess is also a hot lead, and may go directly to some high-current thing—possibly the generator for starting, possibly the inverter if you have one, possibly the converter (particularly if it's a deck-mount converter physically located near the battery), possibly the chassis system via the isolator....

At any rate, wires that go to the chassis connect to the negative of the batteries. (The two six volt batteries are, of course, connected in series to form a single 12V battery that is physically composed of two chunks). Wires that go to something else, with very few rare exceptions, are connected to the positive terminal (and generally should be fused near the battery).

Moved from Forum Technical Support

The positive of one of the batteries goes to the battery disconnect relay. The negative of that battery goes to the positive of the other battery with the short cable(about12 inches long). The negative of the second battery is connected to the frame of the rig.
Your battery disconnect will not operate without power so there is no way to shut power off to the rig.

Boy, that's a tough one for me.

First, turn off EVERYTHING in the coach, then hook up what you think is reasonable without doing any arc welding. Turn on a fan, see if it runs correctly.