I have an off the grid solar house in Baja.

3 panels; 2 deep cycle batteries, inverter which feeds into a box for AC with two circuits coming from that, so two circuit breakers.

2 weeks ago, we arrived to fully charged batteries. In the course of the first night the charge went WAY down. So much that they did not even fully charge in a full day of sun.

We replaced the batteries with charged “loaners” The batteries lost all charge overnight again with only one ceiling fan running.

Next night, same thing without even the fan running.

The current loss is coming through circuit breaker 2. When it is switched off, there is no leak. I checked the breaker. It’s fine.

I checked for voltage in every outlet. One outlet had a high reading in one of the plugs. I removed the outlet and capped off the wires. No change.

My question: How do I find the leak? Once I locate it, I may have a question about how to fix it, but for now, I need to find the leak.