House Battery Problem

[1der]

Originally Posted by CDACamper

1der, the battery is under the barn doors not behind the axle.

Well the battery took a charge and seems normal again. I was getting some odd voltage readings from my battery monitor where it would fluctuate up and down without any load so I am suspecting I have a bad battery monitor, a bad ground or a combination of both. After charging the battery, I am getting a little over 13 volts (measure by volt meter and battery monitor) after letting the battery rest overnight, so it is holding a charge. I also switched on lights and the voltage didn't dip drastically. I haven't load tested it yet.

Question: I currently have the negative ground going from the house battery to the ground shunt. Then from the shunt to the wheel well for the rear tire (grounding to the body (this is where Sportsmobile put the ground originally). The connection looks clean but I imagine that it's not an ideal location. I would rather not run the ground back down through the floor to the frame, but can if that would be advisable. Is there a better place for the main ground inside the van other than the wheel well? I have an e350 EB50.
I know there is a ground strap from the frame to body near my house battery that is the original. I now plan to replace it with a new strap and clean connection surfaces.

Good, seems like a a non-battery issue then and more in the connection/monitor area.

Battery Ground goes directly to one side of the shunt, that is correct, it is the only connection on that side of the shunt. Other terminal of shunt goes to a ground which, yes, SMB loves to use a bolt through the wheel well to ground to the body. As you saw, there are various ground connections from the body to the frame under the van to connect frame to body for ground continuity. Replacing a worn strap is a good idea but likely not the cause of the bad reading.

It would be better to also run a dedicated ground for the load side of the shunt to a bus bar that receives other ground connections from your loads. The battery monitor should have a direct connection to the shunt, correct?

You might be able to reach up and check the terminal connections on the battery to see if they are loose. You could also have a bad positive connection along the circuit.