We have a 2000 Keystone Montana at our property that we use (for now) as a break room/tool room as we prepare to build a new home on the land. This summer I bought a lithium iron phosphate deep cycle battery to replace our old, bad battery. We don't use anything that's 12v in the 5th wheel these days, and the converter hums, so I had assumed all was well until I checked it yesterday. Using my Fluke 115, when I checked the battery while hooked up and shore power coming in, it showed only .814v. When I disconnected the cables from the battery, it reads 10.53v. What is going on here? When we bought the Montana used 5 years ago, we took it to a local shop and everything checked out ok. We don't use the furnace, hot water or fridge currently. It seems the DC lights work, but not all of them. The 12v lights from the steps to the front (bedroom) don't come on. There has been some damage to the wires in the front battery compartment from mice, but I thought I had that straightened out.
So my question is, what could be keeping this battery from getting a full charge when the power to the converter is left on (we have a residential solar set up for the house and shop when they're finished) full time?
The battery is a Grener 100ah LiFePo. I plan on adding a second one later, but since we seldom use any 12v power, I figured I'd try this brand out before I purchase a second. It has great reviews on Amazon, where I bought it. Also, all the 120v lights, outlets and AC work fine, so there's no problem on the AC side. Thanks for any suggestions and ideas. I was really surprised to find it not fully charged, and even more confused about the nearly non-existent reading of .8 volts when hooked up. Lee
