Shore power not charging battery

[ryano2121]

I bought a used FW from a private party a few months ago. We are going boondocking this weekend for the first time in this rig and I found out last night that shore power is not charging my battery. After running the fridge and radio for most of the day, the battery was close to dead even though I was plugged in. The battery will charge when my truck is connected, but that is it.

When connected to shore power and disconnected from the battery, the lights work. When connected to the battery and not to shore power, the lights also work (with a charged battery of course).

I am not sure where to go from here.

[GaryKD]

Hi ryano2121,
Welcome to iRV2. Somewhere in your unit is a charger/converter. Not knowing the details of your RV, there could be a combined charger/converter and inverter.

Consider starting at the 125 VAC breaker panel. There should be a breaker for the converter/charger. Make sure it is reset and on.

Next, find the converter/charger. Make sure it is plugged in and there is power to it (VAC).

Measure the power out of the converter/charger (VDC). If you have power in but no power out, check that the breaker on the converter/charger is reset and on. This is usually a small round button breaker and hard to find. If all this is good, then the converter/charger is suspect.

If you have power out of the converter/charger check for VDC power across the battery terminals. The reading should be the same as the output of the converter/charger. If the VDC power is the same as the output of the converter/charger, the battery(s) are suspect. If the reading is different, there may be a fuse between the converter and the batteries that is blown.

A temporary fix is to put a portable battery charger on the RV battery(s).

[Wayne Pryor]

The converter could have fuses located on it instead of a small breaker. The first thing you have to do is locate the converter. It could be a stand alone located almost anywhere or it could be built into the lower section of your breaker box.